feat: implement chunked storage for Telegram file uploads and retrieval

.gitignore

@@ -23,6 +23,9 @@ report.[0-9]_.[0-9]_.[0-9]_.[0-9]_.json
 .env.production.local
 .env.local
 
+# S3 client guide (local reference)
+S3_GUIDE.md
+
 # caches
 .eslintcache
 .cache