feat: SSH tunnel support

- Add ssh2 dependency for SSH port forwarding
- NewConnectionDialog: SSH toggle + host/port/user/password/privateKey/passphrase form
- connection.ts: createSshTunnel() with local port forwarding
- Connect ioredis through SSH tunnel when sshEnabled
- Clean up SSH client + tunnel server on disconnect
- i18n keys for all SSH fields (zh-CN + en)
- Add sshPassphrase to all ConnectionConfig types

electron/preload/index.d.ts

@@ -16,6 +16,7 @@ export interface ConnectionConfig {
   sshUsername: string
   sshPassword: string
   sshPrivateKeyPath: string
+  sshPassphrase: string
   cluster: boolean
   sentinelMasterName: string
   separator: string