feat: Add centralized logging system with @link-stack/logger package

- Create new @link-stack/logger package wrapping Pino for structured logging
- Replace all console.log/error/warn statements across the monorepo
- Configure environment-aware logging (pretty-print in dev, JSON in prod)
- Add automatic redaction of sensitive fields (passwords, tokens, etc.)
- Remove dead commented-out logger file from bridge-worker
- Follow Pino's standard argument order (context object first, message second)
- Support log levels via LOG_LEVEL environment variable
- Export TypeScript types for better IDE support

This provides consistent, structured logging across all applications
and packages, making debugging easier and production logs more parseable.

packages/zammad-addon-common/package.json

@@ -16,6 +16,7 @@
   "author": "",
   "license": "AGPL-3.0-or-later",
   "dependencies": {
+    "@link-stack/logger": "*",
     "glob": "^11.0.1"
   }
 }