refactor: eliminate as any type casts across 18 source files

- Fix computeDisciplineEffects() to not require GameState parameter
- Fix getUnifiedEffects() to accept proper partial state type
- Replace upgradeEffects as any with proper UnifiedEffects type
- Replace explicit : any annotations with proper types (ComputedEffects, DesignProgress, SpellDef, etc.)
- Fix activity-log.ts eventType casting
- Fix crafting-design.ts computedEffects and designProgress types
- Fix page.tsx grimoire spell rendering with proper SpellDef property names
- Fix StatsTab ManaStatsSection with proper ManaStatsEffects interface
- Remove unused imports (useDisciplineStore from page.tsx, LeftPanel.tsx)

Remaining: 1 as any in craftingStore.ts (pre-existing CraftingStore/GameState architectural mismatch)

src/lib/game/utils/activity-log.ts

@@ -1,7 +1,7 @@
 // ─── Activity Log Helper ───────────────────────────────────────────────
 // Moved from store-modules/activity-log.ts to eliminate legacy dependencies
 
-import type { ActivityLogEntry } from '../types';
+import type { ActivityEventType, ActivityLogEntry } from '../types';
 
 function createActivityEntry(
   eventType: string,
@@ -11,7 +11,7 @@ function createActivityEntry(
   return {
     id: `act_${Date.now()}_${Math.random().toString(36).substr(2, 9)}`,
     timestamp: Date.now(), // Use timestamp for ordering
-    eventType: eventType as any,
+    eventType: eventType as ActivityEventType,
     message,
     details,
   };