feat(web): translate slot, rarity, danger, and location-type labels to English

Translates the four static Angular label maps (SLOT_LABELS, RARITY_LABELS,
DANGER_LABELS, LOCATION_TYPE_LABELS) and the inventory detail panel's
hardcoded item-type fallback per the English Game Content Foundation
design doc glossary. Updates every spec assertion across the web app that
checks rendered text sourced from these maps, including specs owned by
later tasks (combat-page, encounter-card, inventory-page) where they
render one of these labels.

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

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

@@ -149,9 +149,9 @@ describe('InventoryPageComponent', () => {
     const { fixture } = await setup();
     const text = (fixture.nativeElement as HTMLElement).querySelector('.inventory-page__equipment-list')?.textContent ?? '';
 
-    expect(text).toContain('Waffe');
+    expect(text).toContain('Weapon');
     expect(text).toContain('Abgenutztes Kurzschwert');
-    expect(text).toContain('Kopf');
+    expect(text).toContain('Head');
     expect(text).toContain('Leer');
   });