refactor: extract Discord.js code from shared services into bot layer

Move terminal.service.ts and prune.service.ts entirely to bot/modules/
since they are Discord-specific. Split lootdrop.service.ts: pure logic
(activity tracking, DB ops, claim) stays in shared/, Discord operations
(message sending, channel interactions) move to bot/modules/economy/
lootdrop.handler.ts. Move effect registry/handlers/types from bot/ to
shared/modules/inventory/ since they contain no Discord.js imports and
are needed by inventory.service.ts in shared.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

shared/modules/inventory/inventory.service.ts

@@ -170,7 +170,7 @@ export const inventoryService = {
             const results: any[] = [];
 
             // 2. Apply Effects
-            const { validateAndExecuteEffect } = await import("@/modules/inventory/effect.registry");
+            const { validateAndExecuteEffect } = await import("./effect.registry");
 
             for (const effect of usageData.effects) {
                 const result = await validateAndExecuteEffect(effect, userId, txFn);