Refactors `ChannelsTable.js` to ensure that the selected group filter is **never lost** when:
1. Cycling between channel-type tabs.
2. Changing the status dropdown (all / enabled / disabled).
Key points:
• `loadChannels` now detects active search filters (keyword / group / model) and transparently delegates to `searchChannels`, guaranteeing all parameters are sent in every request.
• `searchChannels` accepts optional `typeKey` and `statusF` arguments, enabling reuse without code duplication.
• Loading state handling is unified; no extra renders or side effects were introduced, keeping UI performance intact.
• Duplicate logic removed and responsibilities clearly separated for easier future maintenance.
