feat: multi-format viewer (Text/Hex/JSON/Binary/Gzip/Deflate/Brotli)

- New format.ts: decodeValue + detectFormat using Node.js zlib
- IPC: redis:decodeValue, redis:detectFormat
- StringEditor: format selector dropdown with auto-detect
- Monaco editor shows decoded value, read-only for compressed formats
- Auto-detect: JSON, Gzip (1f 8b), Deflate (78 xx), non-printable → Hex
- i18n keys for all formats (zh-CN + en)

electron/main/redis/index.ts

@@ -11,3 +11,4 @@ export * from './stream'
 export * from './server'
 export * from './commandLogger'
 export * from './pubsub'
+export * from './format'