refactor: atomic, DRY, and logging improvements across codebase

- Split llmModerationClient.ts (2170 lines) into 5 focused sub-modules
- Split aiAnalyzer.ts (1282 lines) into 4 modular pipelines
- Split messages.db.ts (826 lines) into 5 domain-specific modules
- Moved shared schema to @bete/shared, eliminated backend duplication
- Added createChildLogger to all voice-recording and AI moderation modules
- Extracted tryCommandThenFallback, normalizeMediaState, DEFAULT_VOICE_STATUS
- Created shared pagination.ts utility, eliminated 5+ cursor-pagination duplications
- Created shared messageMapper.ts for row mapping
- Standardized backend error handling with asyncHandler
- Added frontend createLogger utility and useAsyncAction hook
- Added structured logging to frontend hooks, socket, and API client

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

packages/shared/package.json

@@ -8,6 +8,7 @@
   "exports": {
     ".": "./dist/index.js",
     "./config": "./dist/config/index.js",
+    "./database/schema": "./dist/database/schema.js",
     "./errors": "./dist/errors/index.js",
     "./logger": "./dist/logger/index.js",
     "./utils": "./dist/utils/index.js"
@@ -17,6 +18,7 @@
     "typecheck": "tsc --noEmit"
   },
   "dependencies": {
+    "drizzle-orm": "^0.45.2",
     "pino": "^9.0.0",
     "zod": "^4.4.3"
   },