fix: address final-review findings (TopBar hydration, snapshot test, armor doc, inventory refresh test)

Fixes 4 Important findings from the final whole-branch review:
- /inventory never called WorldStore.load(), leaving the TopBar stuck on
  "loading" and characterLevel() silently defaulting to 1 for any character
  above level 1. Mirrors the same guard already used in HuntPageComponent.
- The combat/equipment snapshot-immutability integration test asserted only
  status/round, never the actual playerState snapshot the whole test claims
  to prove is untouched after a post-fight equip.
- Documented (comment only, no behavior change) that the demo character's
  armor dropping from the old hardcoded 6 to 0 is an intentional,
  spec-sanctioned tradeoff (Slice 0.5 spec Section19), not a bug.
- inventory.store.spec.ts's equip test used an identical inventory fixture
  before and after equip(), so a regression dropping the post-equip
  inventory re-fetch would still have passed. Now asserts the refetched
  fixture is actually reflected.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

apps/web/src/app/features/inventory/inventory-page.component.spec.ts

@@ -76,6 +76,7 @@ interface SetupOptions {
   inventoryData?: InventoryResponse;
   selectedItemId?: string | null;
   selectedItem?: InventoryItem | null;
+  character?: CharacterResponse | null;
 }
 
 async function setup(options: SetupOptions = {}) {
@@ -91,7 +92,10 @@ async function setup(options: SetupOptions = {}) {
     selectedItem: vi.fn(() => options.selectedItem ?? null),
     equip: vi.fn(() => Promise.resolve()),
   };
-  const worldStore = { character: signal(character) };
+  const worldStore = {
+    character: signal(options.character === undefined ? character : options.character),
+    load: vi.fn(() => Promise.resolve()),
+  };
 
   await TestBed.configureTestingModule({
     imports: [InventoryPageComponent],
@@ -103,7 +107,7 @@ async function setup(options: SetupOptions = {}) {
 
   const fixture = TestBed.createComponent(InventoryPageComponent);
   fixture.detectChanges();
-  return { fixture, inventoryStore };
+  return { fixture, inventoryStore, worldStore };
 }
 
 describe('InventoryPageComponent', () => {
@@ -112,6 +116,16 @@ describe('InventoryPageComponent', () => {
     expect(inventoryStore.load).toHaveBeenCalledOnce();
   });
 
+  it('loads the world state on init when no character has been loaded yet (direct navigation/hard refresh)', async () => {
+    const { worldStore } = await setup({ character: null });
+    expect(worldStore.load).toHaveBeenCalledOnce();
+  });
+
+  it('does not call world load again when a character is already present', async () => {
+    const { worldStore } = await setup();
+    expect(worldStore.load).not.toHaveBeenCalled();
+  });
+
   it('renders one tile per owned item', async () => {
     const { fixture } = await setup();
     const tiles = (fixture.nativeElement as HTMLElement).querySelectorAll('.inventory-page__slot');

apps/web/src/app/features/inventory/inventory-page.component.ts

@@ -52,6 +52,9 @@ export class InventoryPageComponent implements OnInit {
   });
 
   ngOnInit(): void {
+    if (this.worldStore.character() === null) {
+      void this.worldStore.load();
+    }
     void this.inventoryStore.load();
   }
 

apps/web/src/app/features/inventory/inventory.store.spec.ts

@@ -65,6 +65,13 @@ const equippedAfter: EquipmentResponse = {
   stats: { maxHp: 100, attack: 7, weaponDamage: 11, armor: 0 },
 };
 
+const inventoryAfterEquip: InventoryResponse = {
+  items: [
+    { ...inventory.items[0], equipped: false },
+    { ...inventory.items[1], equipped: true },
+  ],
+};
+
 describe('InventoryStore', () => {
   let api: {
     getInventory: ReturnType<typeof vi.fn>;
@@ -109,12 +116,19 @@ describe('InventoryStore', () => {
   });
 
   it('equips the selected item, refreshes inventory/equipment, and refreshes the character HUD', async () => {
+    api.getInventory
+      .mockReturnValueOnce(of(inventory)) // initial load()
+      .mockReturnValueOnce(of(inventoryAfterEquip)); // post-equip refetch
+
     await store.load();
 
     await store.equip('item-blade');
 
     expect(api.equipItem).toHaveBeenCalledWith('item-blade');
     expect(store.equipment()).toEqual(equippedAfter);
+    expect(store.inventory()).toEqual(inventoryAfterEquip);
+    expect(store.inventory()?.items.find((item) => item.id === 'item-sword')?.equipped).toBe(false);
+    expect(store.inventory()?.items.find((item) => item.id === 'item-blade')?.equipped).toBe(true);
     expect(worldStore.refreshCharacter).toHaveBeenCalledOnce();
   });