fix: visually block off-hand slot when 2H weapon equipped in main hand

- Add getTwoHandedBlocker() helper to EquipmentSlotGrid that detects when
  mainHand has a two-handed weapon and returns the weapon name
- Render offHand slot with Lock icon + 'Blocked: <weapon name>' label +
  reduced opacity when blocked, distinct from normal 'Empty' dashed-border slot
- Add regression test verifying all 4 two-handed types are correctly flagged
  and non-two-handed types remain unblocked (11 tests)

docs/circular-deps.txt

@@ -1,5 +1,5 @@
 # Circular Dependencies
-Generated: 2026-06-09T12:49:08.595Z
+Generated: 2026-06-09T13:31:30.036Z
 Found: 2 circular chain(s) — these MUST be fixed before modifying involved files.
 
 1. 1) stores/golem-combat-actions.ts > stores/golem-combat-helpers.ts

docs/dependency-graph.json

@@ -1,6 +1,6 @@
 {
   "_meta": {
-    "generated": "2026-06-09T12:49:06.615Z",
+    "generated": "2026-06-09T13:31:28.048Z",
     "description": "Import dependency graph for src/lib/game. Keys are files, values are arrays of files they import.",
     "usage": "To find what a file affects, search for its path in the VALUES. To find what a file depends on, look at its KEY entry."
   },

docs/project-structure.txt

@@ -96,6 +96,7 @@ Mana-Loop/
 │   │   │   │   │   └── SpireDebugSection.tsx
 │   │   │   │   ├── EquipmentTab/
 │   │   │   │   │   ├── EquipmentEffectsSummary.tsx
+│   │   │   │   │   ├── EquipmentSlotGrid.test.ts
 │   │   │   │   │   ├── EquipmentSlotGrid.tsx
 │   │   │   │   │   └── InventoryList.tsx
 │   │   │   │   ├── SpireCombatPage/