Add building status light

src/ui/GameWorldView.cpp

@@ -124,6 +124,20 @@ QPoint portBodyTile(QPoint portTile, Rotation direction)
     return portTile;
 }
 
+// Fill color for a building's status light per its production state
+// (REQ-UI-STATUS-LIGHT).
+QColor statusLightFill(ProductionStatus status, const StatusLightVisuals& sl)
+{
+    switch (status)
+    {
+    case ProductionStatus::Unconfigured: return sl.grey;
+    case ProductionStatus::Producing:    return sl.green;
+    case ProductionStatus::Starved:      return sl.red;
+    case ProductionStatus::Blocked:      return sl.yellow;
+    }
+    return sl.grey;
+}
+
 }  // namespace
 
 
@@ -1039,6 +1053,35 @@ void GameWorldView::drawBuildings(QPainter& painter)
                           port.direction, bv.outline, /*centered*/ false);
         }
 
+        // Status light: a small circle in the building's upper-right corner
+        // (in default/East orientation), anchored to that footprint corner and
+        // rotating with the building (REQ-UI-STATUS-LIGHT). All status-light
+        // building footprints are rectangular, so a corner of the axis-aligned
+        // bounding box is the true corner.
+        if (const std::optional<ProductionStatus> status =
+                m_sim->getBuildings().getProductionStatus(b))
+        {
+            const float px    = getTilePx();
+            const float r     = px * 0.18f;
+            const float inset = r + px * 0.12f;
+            // Default orientation (East) puts the light at the top-right corner;
+            // clockwise rotation carries it around the footprint.
+            QPointF center(bboxRect.right() - inset, bboxRect.top() + inset);
+            switch (b.rotation)
+            {
+            case Rotation::East:  break;
+            case Rotation::South: center = QPointF(bboxRect.right() - inset,
+                                                   bboxRect.bottom() - inset); break;
+            case Rotation::West:  center = QPointF(bboxRect.left() + inset,
+                                                   bboxRect.bottom() - inset); break;
+            case Rotation::North: center = QPointF(bboxRect.left() + inset,
+                                                   bboxRect.top() + inset); break;
+            }
+            painter.setBrush(statusLightFill(*status, m_visuals->statusLight));
+            painter.setPen(QPen(m_visuals->statusLight.outline, 1));
+            painter.drawEllipse(center, r, r);
+        }
+
         // HP bar below the HQ footprint; the HQ's HP lives on its proxy entity.
         if (b.type == BuildingType::Hq)
         {

src/ui/VisualsConfig.h

@@ -60,6 +60,17 @@ struct ToastVisuals
     int    fontSize;
 };
 
+// Fill colors for the building status light (REQ-UI-STATUS-LIGHT), plus its
+// constant outline color.
+struct StatusLightVisuals
+{
+    QColor grey;    // no recipe/schematic selected
+    QColor green;   // producing
+    QColor red;     // idle, input missing (or Salvage Bay empty)
+    QColor yellow;  // idle, output buffer full
+    QColor outline;
+};
+
 struct VisualsConfig
 {
     TileVisuals asteroid;
@@ -69,7 +80,8 @@ struct VisualsConfig
     std::map<std::string,  ItemVisuals>     items;
     std::map<std::string,  ShipVisuals>     ships;
 
-    BeamVisuals    beams;
-    OverlayVisuals overlays;
-    ToastVisuals   toast;
+    BeamVisuals        beams;
+    OverlayVisuals     overlays;
+    ToastVisuals       toast;
+    StatusLightVisuals statusLight;
 };

src/ui/VisualsLoader.cpp

@@ -237,5 +237,15 @@ VisualsConfig VisualsLoader::load(const std::string& path)
         cfg.toast.fontSize = requireInt(t, "font_size", "toast");
     }
 
+    // Status light (REQ-UI-STATUS-LIGHT)
+    {
+        toml::table& sl = requireSubtable(tbl, "status_light", "root");
+        cfg.statusLight.grey    = parseColor(requireString(sl, "grey",    "status_light"), "status_light.grey");
+        cfg.statusLight.green   = parseColor(requireString(sl, "green",   "status_light"), "status_light.green");
+        cfg.statusLight.red     = parseColor(requireString(sl, "red",     "status_light"), "status_light.red");
+        cfg.statusLight.yellow  = parseColor(requireString(sl, "yellow",  "status_light"), "status_light.yellow");
+        cfg.statusLight.outline = parseColor(requireString(sl, "outline", "status_light"), "status_light.outline");
+    }
+
     return cfg;
 }