* refactor(web): load channel configs without exposing secret values
- add a dedicated channel config API that returns sanitized config plus
configured secret metadata
- update channel config pages and forms to use secret presence for
placeholders, validation, reset, and save behavior
- refresh the channel settings layout and clean up related i18n copy
- add backend tests for the new channel config endpoint
* fix(config): restore missing strings import
- persist Weixin bindings, enable the channel automatically, and try to restart the gateway
- refresh frontend channel and gateway state after successful binding
- harden QR polling state handling and update related channel UI behavior
- localize sidebar channel priority, add Weixin icon support, and add backend test coverage
