state only the yields a recipe can actually be made to give

A Reprocessing Plant advertised every item its recipe lists, voidsteel included,
while the pool would never pick a group holding a locked item -- so the summary
promised a yield the building could not produce, and disagreed with the output
buffers below it, which listed unlocked items only.

Three places drew those groups: the panel summary, the option button that offers
the recipe, and the item tooltip's producer line. All three now go through
toUnlockedOutputGroups, which drops a group whole exactly as the pool does.

It asks of every group, single-group recipes included, where the pool exempts
them. That exemption exists so a building whose one output nothing yet demands
still produces -- a rule about running, not about what to state. What makes the
stricter rule safe to state is that no building can hold a recipe with nothing
left to draw: the dialog does not offer one, auto-selection does not adopt one,
and the blueprint gate does not apply one.

The tooltip needed one more condition. A recipe listing the item only in a group
holding something locked is no path to that item at all, so it is no longer
listed as a producer of it -- otherwise the line drawn beneath the recipe's name
would not have named the item it was opened to explain.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Ne3mejABZoLWKLh8fgpM3x

docs/requirements.md

@@ -653,7 +653,9 @@ The panel shows exactly one **content** at a time, picked from the catalog in RE
   Input and output chips form separately captioned sections (REQ-UI-SELECTION-CARD). A section lists a chip for **every item the building's cycle involves**, whether or not the buffer currently holds any: an empty buffer reads `0` rather than its chip disappearing, so the card keeps one shape while the building runs. A section left with no chips at all is not shown. The production section (REQ-UI-PRODUCTION-PROGRESS) sits **between them**, so the card reads in the direction the materials flow: what goes in, what is being made of it, what has come out. For a selected construction site the buffer sections are omitted (REQ-BLD-SITE-CONFIG).
 
   **Only unlocked items are listed.** Should a building's buffers carry an entry for an item the player cannot make yet, it is left out of both sections, consistent with the rest of the UI hiding what is not unlocked yet (REQ-LOCK-UI-RECIPE, REQ-LOCK-UI-SPLITTER).
-- REQ-UI-RECIPE-SUMMARY: Below the recipe/schematic selection control, a building running a recipe or schematic shows a one-line **recipe summary**: each input item's icon on its colored square (REQ-UI-ITEM-ICON) with its per-cycle amount and the inputs separated by `+`, an arrow, then what the recipe produces, and the cycle time in seconds. The output side lists each item of an output group with its icon and per-cycle amount, the items within a group separated by `+` as the inputs are — they are produced together — and the **groups separated by `/`**, since only one of them happens (REQ-MAT-OUTPUT-GROUP). A recipe with a single group therefore reads exactly as before, and a Reprocessing Plant's reads as the alternatives it is rather than as one combined yield. It restates what the building will do without opening the selection dialog, and it is the panel's only display of the cycle time. Each input and output icon names an item and explains it on hover or click, together with the amount beside it (REQ-UI-ITEM-VALUE-TOOLTIP) — so the summary is also where the player follows a recipe's inputs back to what makes them, without the item having to be in a buffer to be asked about. For a Shipyard the summary is built from the schematic's materials and production time including the placed modules' contributions (REQ-BLD-SHIPYARD, REQ-MOD-STAT-CALC), matching the buffers beneath it. A building with no recipe or schematic selected shows no summary — including an auto-recipe building that has yet to select one (REQ-BLD-AUTO-RECIPE), which shows none until it does and keeps it from then on, so the card does not resize in step with the building's status (REQ-UI-SELECTION-STATUS, REQ-UI-SELECTION-PANEL).
+- REQ-UI-RECIPE-SUMMARY: Below the recipe/schematic selection control, a building running a recipe or schematic shows a one-line **recipe summary**: each input item's icon on its colored square (REQ-UI-ITEM-ICON) with its per-cycle amount and the inputs separated by `+`, an arrow, then what the recipe produces, and the cycle time in seconds. The output side lists each item of an output group with its icon and per-cycle amount, the items within a group separated by `+` as the inputs are — they are produced together — and the **groups separated by `/`**, since only one of them happens (REQ-MAT-OUTPUT-GROUP). A recipe with a single group therefore reads exactly as before, and a Reprocessing Plant's reads as the alternatives it is rather than as one combined yield.
+
+  **Only groups the player could be handed are stated.** A group holding any locked item is left out whole, exactly as the pool leaves it out when picking (REQ-LOCK-OUTPUT-POOL) — a summary that advertised it would promise a yield the building will never produce, and would disagree with the output buffers beneath it, which list unlocked items only (REQ-UI-SINGLE-SELECTION). A Reprocessing Plant therefore states three alternatives where its recipe lists four and the fourth is still locked. Unlike the pool, the test applies to a single-group recipe too: the pool exempts those so that a building whose one output nothing yet demands still produces, which is a rule about what to run, not about what to state. A recipe left with no group at all would have nothing to draw, but none can be selected, adopted, or applied from a blueprint (REQ-LOCK-UI-RECIPE, REQ-BLD-AUTO-RECIPE, REQ-LOCK-UI-BLUEPRINT), so no building holds one. It restates what the building will do without opening the selection dialog, and it is the panel's only display of the cycle time. Each input and output icon names an item and explains it on hover or click, together with the amount beside it (REQ-UI-ITEM-VALUE-TOOLTIP) — so the summary is also where the player follows a recipe's inputs back to what makes them, without the item having to be in a buffer to be asked about. For a Shipyard the summary is built from the schematic's materials and production time including the placed modules' contributions (REQ-BLD-SHIPYARD, REQ-MOD-STAT-CALC), matching the buffers beneath it. A building with no recipe or schematic selected shows no summary — including an auto-recipe building that has yet to select one (REQ-BLD-AUTO-RECIPE), which shows none until it does and keeps it from then on, so the card does not resize in step with the building's status (REQ-UI-SELECTION-STATUS, REQ-UI-SELECTION-PANEL).
 - REQ-UI-PRODUCTION-PROGRESS: For buildings that produce items or ships (miner, smelter, assembler, reprocessing plant, shipyard), the panel's runtime group shows a captioned **production section** between the input and output buffer sections (REQ-UI-SINGLE-SELECTION): a horizontal progress bar filled to the completion of the active production cycle, with that completion beside the caption as an integer percentage (e.g. `72%`), or the text `idle` in place of the percentage and an empty bar when no production cycle is active. The cycle time is shown in the recipe summary (REQ-UI-RECIPE-SUMMARY) rather than repeated here. When no recipe or schematic is selected, the production section is not shown at all.
 - REQ-UI-MULTI-SELECT: The player selects multiple objects by box-drag or by Ctrl+clicking individual objects to add or remove them from the selection. Multi-select operates within a single category (REQ-UI-SELECTION-CATEGORIES). A box-drag that covers at least one building selects buildings (any field objects within the box are ignored — buildings win); a box-drag that covers no building but does cover ships, defence stations, or debris selects all of those field objects together (REQ-UI-ENTITY-CLICK-SELECT, REQ-UI-DEBRIS-MULTI-SELECT).
   - **Rectangle geometry.** The box is **not** snapped to tiles: its two corners are the exact world positions the button went down at and the cursor is at now, so the rectangle is drawn where the mouse actually went and follows it pixel by pixel. The corners are held in world coordinates rather than screen ones, so the anchor stays on the spot in the world it was placed on when the view scrolls under a held button (REQ-UI-SCROLL).
@@ -664,14 +666,14 @@ The panel shows exactly one **content** at a time, picked from the catalog in RE
 - REQ-UI-CONFIG-INLINE: Recipe and schematic configuration for a selected building is shown within this panel, in its configuration group (REQ-UI-SELECTION-CARD). Recipe selection (miner, assembler, smelter, reprocessing plant) and schematic selection (shipyard) use the selection button and dialog (REQ-UI-SELECT-BUTTON) rather than an inline control. For shipyards, the panel additionally shows the ship layout preview and "Configure" button below the schematic selection button (REQ-MOD-UI-PREVIEW).
 - REQ-UI-SELECT-BUTTON: **Recipe and schematic selection control.** Recipe selection (Miner ore type, Assembler recipe, and the Smelter's and Reprocessing Plant's recipe per REQ-BLD-AUTO-RECIPE) and schematic selection (Shipyard) are each presented in the selection panel as a single **selection button** whose caption is the name of the currently selected recipe or schematic, or a placeholder ("Select recipe" / "Select schematic") when none is selected. Clicking the button opens a modal **selection dialog** that pauses the game (speed set to 0×; on close, the speed is restored to what it was before the dialog was opened) and that opens centered on the selection panel, as every modal opened from the panel does (REQ-UI-PANEL-MODAL). The dialog contains a vertical list of option buttons, one per selectable option, each describing itself (REQ-UI-SELECT-OPTIONS) — only options that are currently unlocked are shown (REQ-LOCK-UI-RECIPE for recipes, REQ-LOCK-UI-SCHEMATIC for schematics). Neither the option buttons nor the selection button carries a tooltip **of its own** — the items they name explain themselves as they do everywhere else (REQ-UI-ITEM-VALUE-TOOLTIP), which is a different question from what the option does: an option button states what it makes on its own face, and what the building has selected is drawn beneath the selection button as the recipe summary (REQ-UI-RECIPE-SUMMARY), with the production paths of the items involved reachable from that summary's own icons and from the card's item chips (REQ-UI-ITEM-TOOLTIP, REQ-UI-ITEM-VALUE-TOOLTIP). Clicking an option button selects that recipe/schematic, closes the dialog, and updates the selection button's caption in the selection panel. The dialog can be dismissed without changing the current selection — by closing it without clicking an option, by Escape, by Q, or by clicking outside it (REQ-UI-DIALOG-DISMISS). Selecting a new recipe or schematic has the same effects as before (REQ-MAT-INPUT-BUFFER, REQ-MAT-OUTPUT-BUFFER, REQ-BLD-SHIPYARD).
 - REQ-UI-SELECT-OPTIONS: **Option list of the selection dialog.** The selection dialog (REQ-UI-SELECT-BUTTON) lists its options as a **single vertical column** of buttons, one per option, rather than a grid: each button is as wide as the dialog and states what the option does, which needs a line of its own. No option button carries a tooltip describing the option — the button face is the whole description, so the player reads every option's inputs, product, and time from the list itself without hovering anything. What the button face does not say is where an input comes from, and that the items it names answer themselves, on hover (REQ-UI-ITEM-VALUE-TOOLTIP): the click stays the gesture that picks the option. Should the column be taller than the space the window leaves the dialog — a fully unlocked Assembler offers more options than any window can hold, and a modal is never resized to fit (REQ-UI-PANEL-MODAL) — the list **scrolls** within the dialog rather than the dialog growing past the window.
-  - A **recipe** option shows the **recipe name** on its first line and, beneath it, that recipe drawn as the recipe summary line draws it (REQ-UI-RECIPE-SUMMARY): each input item's icon on its colored square with its per-cycle amount, an arrow, its output groups with their amounts, and the cycle time. A miner recipe consumes nothing, so its line begins at the arrow.
+  - A **recipe** option shows the **recipe name** on its first line and, beneath it, that recipe drawn as the recipe summary line draws it (REQ-UI-RECIPE-SUMMARY): each input item's icon on its colored square with its per-cycle amount, an arrow, its output groups with their amounts, and the cycle time. That includes the summary's rule on which groups are stated at all, so an option states what choosing it would actually get the player, and the panel states the same thing afterwards. A miner recipe consumes nothing, so its line begins at the arrow.
   - A **ship schematic** option (Shipyard) shows the ship's `display_name` on its first line and, beneath it, the icons and quantities of its base required materials (`[ship.schematic].materials`, excluding any module contributions) with the base production time (`[ship.schematic].production_time_seconds`). A ship is not an item and has no icon of its own, so this line names no output: the button's caption is what it produces.
   - The `(None)` option shows its text caption alone. On an auto-recipe building it is captioned `(Auto)` instead, because there it does not leave the building idle but returns it to automatic selection (REQ-BLD-AUTO-RECIPE).
 - REQ-UI-ITEM-TOOLTIP: **Item production tooltip.** Hovering an item chip in the selection panel — an input or output buffer chip (REQ-UI-SINGLE-SELECTION) or the HQ's block stock chip (REQ-UI-HQ-PANEL) — shows a tooltip telling the player where that item comes from. A chip has no click action of its own, so clicking one shows the same tooltip at once (REQ-UI-TOOLTIP-TRIGGER, REQ-UI-TOOLTIP-DISMISS). It has a heading and a body:
   - the heading is the **chip's item name**. For an input chip this is the only place the item is named at all, since such a chip carries a count and no name (REQ-UI-SINGLE-SELECTION).
   - the body is the caption `Produced by` followed by one **recipe line** per unlocked recipe that produces the item. A recipe line is a small **card** of two rows: the icon of the building that runs the recipe (REQ-UI-BUILD-ICON) and the recipe's name on the first, and the recipe itself on the second, drawn as the recipe summary draws it (REQ-UI-RECIPE-SUMMARY) — each input item's icon on its colored square with its per-cycle amount, the inputs separated by `+`, an arrow, its output groups with their amounts, and the cycle time. Two rows rather than one because an identity and a cycle read as different things, and a single row of icons, names and numbers runs too long to scan; a card around each because several producers stacked as bare lines read as one field of icons and numbers rather than as separate recipes. A line drawn where its surroundings already frame it — on an option button (REQ-UI-SELECT-OPTIONS), or as the panel's recipe summary — takes no card of its own. An item may have several producers — an iron ingot is smelted from ore, smelted from scrap, and recovered by reprocessing — and the building icon and recipe name are what tell those lines apart and tell the player which building to place for which path.
 
-  **Only recipes the player can run are listed**, consistent with the rest of the UI hiding what the player cannot make yet. Two conditions, both required and both applying to every building alike: the recipe is unlocked (REQ-LOCK-UI-RECIPE), and the building that runs it can be placed (REQ-LOCK-BUILDING) — there is no sense in naming a path through a plant the player cannot build. Two cases have no recipe line to show, and each says so in place of the list rather than leaving the tooltip bare:
+  **Only recipes that are a path to this item are listed**, consistent with the rest of the UI hiding what the player cannot make yet. Three conditions, all required and all applying to every building alike: the recipe is unlocked (REQ-LOCK-UI-RECIPE); the building that runs it can be placed (REQ-LOCK-BUILDING) — there is no sense in naming a path through a plant the player cannot build; and some output group the pool would pick actually yields the item (REQ-LOCK-OUTPUT-POOL). The third matters where a recipe lists the item only in a group holding something still locked: the pool drops that group whole, so the recipe is no path to the item, whatever its config says. It follows that the line drawn for a listed producer always states at least one group, and that the group naming the item is among those drawn. Two cases have no recipe line to show, and each says so in place of the list rather than leaving the tooltip bare:
   - **An item no recipe produces at all.** Scrap is salvaged from debris (REQ-RES-DEBRIS-DROP) rather than crafted, so its tooltip reads `Salvaged from debris` in place of the `Produced by` caption and lists nothing beneath it.
   - **An item whose every producing recipe is still locked.** The caption stays `Produced by`, and the single line beneath it reads `Undiscovered`: the player is told the item is made somehow, without being shown a path they have not unlocked yet.