dedupe AttackExecutor and RepairExecutor via executeOrbitAndAssign

The two executors were line-for-line duplicates: orbit the behavior target,
then hand it to the owner's in-range modules. Both now call a templated
executeOrbitAndAssign<Behavior, ModuleComponent>; the view types, iteration
order, and sequence of component writes are unchanged.

Co-Authored-By: Claude <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GH8ZMRY3vhxxXcaUxBqxkk

src/lib/ecs/system/ai/OrbitAndAssignExecutor.h

@@ -0,0 +1,89 @@
+#pragma once
+
+#include <QVector2D>
+
+#include "entt/entity/entity.hpp"
+
+#include "BehaviorKind.h"
+#include "DynamicBodyComponent.h"
+#include "EntityAdmin.h"
+#include "ModuleOwnerComponent.h"
+#include "MovementIntentComponent.h"
+#include "PositionComponent.h"
+#include "SelectedBehaviorComponent.h"
+
+// Shared executor body for the behaviors that orbit a single target entity and then
+// hand that target to the ship's in-range modules (REQ-SHP-ORBIT): Attack (with
+// WeaponComponent) and Repair (with RepairToolComponent).
+//
+// Two passes, in this order — the order and the exact sequence of component writes
+// are load-bearing for determinism (see the Tick Order section of
+// docs/architecture.md):
+//   1. Ships that have `Behavior` and won with `kind` write their MovementIntent to
+//      orbit the behavior's target at the behavior's orbit radius. A target that is
+//      gone (or has no position) degenerates to "hold position": the ship's own
+//      position with a zero radius.
+//   2. Modules of type `ModuleComponent` whose owner won with `kind` adopt the
+//      behavior's target, but only when it lies within that module's own range.
+//      Out-of-range modules keep whatever target they already had, which
+//      CombatSystem/RepairSystem re-validate.
+//
+// `Behavior` must expose `std::optional<entt::entity> currentTarget` and
+// `float orbitRadius_tiles`; `ModuleComponent` must expose `float range_tiles` and
+// `std::optional<entt::entity> currentTarget`.
+template <typename Behavior, typename ModuleComponent>
+void executeOrbitAndAssign(EntityAdmin& admin, BehaviorKind kind)
+{
+    // Ships: move toward the behavior target.
+    admin.forEach<Behavior, SelectedBehaviorComponent, PositionComponent,
+                  MovementIntentComponent>(
+        [&](entt::entity /*e*/, const Behavior& behavior,
+            const SelectedBehaviorComponent& selected, const PositionComponent& pos,
+            MovementIntentComponent& intent)
+        {
+            if (selected.winner != kind) { return; }
+            if (!behavior.currentTarget) { return; }
+
+            const entt::entity t = *behavior.currentTarget;
+            QVector2D center = pos.value;
+            float     radius = 0.0f;
+            QVector2D centerVelocity;
+            if (admin.isValid(t) && admin.hasAll<PositionComponent>(t))
+            {
+                center = admin.get<PositionComponent>(t).value;
+                radius = behavior.orbitRadius_tiles;
+                if (admin.hasAll<DynamicBodyComponent>(t))
+                {
+                    centerVelocity = admin.get<DynamicBodyComponent>(t).velocity_tpt;
+                }
+            }
+            intent = MovementIntentComponent{true, center, radius, centerVelocity};
+        });
+
+    // Modules: assign the behavior target only if it is within this module's range.
+    admin.forEach<ModuleComponent, ModuleOwnerComponent>(
+        [&](entt::entity /*me*/, ModuleComponent& module,
+            const ModuleOwnerComponent& owner)
+        {
+            if (!admin.hasAll<Behavior, SelectedBehaviorComponent>(owner.owner))
+            {
+                return;
+            }
+            const SelectedBehaviorComponent& selected =
+                admin.get<SelectedBehaviorComponent>(owner.owner);
+            if (selected.winner != kind) { return; }
+
+            const Behavior& behavior = admin.get<Behavior>(owner.owner);
+            if (!behavior.currentTarget) { return; }
+
+            const entt::entity t = *behavior.currentTarget;
+            if (!admin.isValid(t) || !admin.hasAll<PositionComponent>(t)) { return; }
+
+            const QVector2D ownerPos = admin.get<PositionComponent>(owner.owner).value;
+            const float dist = (admin.get<PositionComponent>(t).value - ownerPos).length();
+            if (dist <= module.range_tiles)
+            {
+                module.currentTarget = t;
+            }
+        });
+}