feat: unify 3 bot services into single process

- Add UNIFIED_MODE flag (default on, disable with UNIFIED_MODE=0)
- Register all 3 Discord bots in one process (claude, codex, review)
- Load all registered groups regardless of agent_type (codex/owner priority)
- Start credential proxy and container cleanup at unified startup
- shouldServiceProcessChat returns true in unified mode
- Add findChannelByName for role-based response routing
- Backward compatible: UNIFIED_MODE=0 restores per-service behavior

src/service-routing.ts

@@ -4,6 +4,7 @@ import {
   CODEX_REVIEW_SERVICE_ID,
   SERVICE_AGENT_TYPE,
   SERVICE_ID,
+  UNIFIED_MODE,
   normalizeServiceId,
 } from './config.js';
 import {
@@ -142,6 +143,7 @@ export function shouldServiceProcessChat(
   chatJid: string,
   serviceId: string = SERVICE_ID,
 ): boolean {
+  if (UNIFIED_MODE) return true;
   const normalizedServiceId = normalizeServiceId(serviceId);
   const lease = getEffectiveChannelLease(chatJid);
   return (