feat(ui-core,ui-lvgl): channel management in the Core, L2 channel screens

ChannelControl (add Public/Hashtag/Private, rename, delete, notif/fav/scope)
and Favourites slots move into ui-core; ui-new uses them. Contact / channel
pref cleanup moves from ui-new's UITask into UiCore so it runs on every
frontend (L2 had none). L2: channel options popup (hold a row or the gear
in a channel) and the Add / Edit channel form.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/design/solo_ui_framework.md

@@ -358,8 +358,9 @@ with `resolvePersonPos()` (live `[LOC]` share, else last-advertised fix).
   (the ringtone player moved to a hardware timer for this reason).
 - **Reference cleanup.** Anything that remembers a contact by pubkey (favourite
   slot, Locator/Live-Share target, per-contact mute/melody) or a channel by
-  index must drop that reference when the entity goes away — hook
-  `UITask::onContactRemoved()` / `onChannelRemoved()`. New per-contact or
+  index must drop that reference when the entity goes away. The UI Core does
+  it for every frontend: `UiCore::cleanupContactPrefs()` (ui-core/UiCore.h) and
+  `chanctl::onRemoved()` (ui-core/ChannelControl.h). New per-contact or
   per-channel state should clear there too.
 - **Toasts:** `_task->showAlert("msg", duration_ms)` overlays a transient banner
   over any screen; no redraw plumbing needed.

docs/development/l2-hardware-checklist.md

@@ -42,6 +42,16 @@ Confirmed: green dot inside the ring, waypoints much better, download works, set
 - [ ] Settings > Radio: Preset list (built-ins + your saved ones), Frequency (tap, type), SF, Bandwidth, Coding rate, TX power, Auto power; changes apply at once — check messages still flow after switching back to your usual preset
 - [ ] L1 (ui-new): Settings > Radio TX power / Auto power / presets still apply (now through the shared RadioControl)
 
+## New: Channels (2026-09-25)
+- [ ] Messages: favourite channels first with a star, muted ones with a speaker icon
+- [ ] Hold a channel row (or ⚙ in an open channel) → options: Alerts (Default / Muted / Always, one tap), Scope (only if regions exist), Fav, Read (only with unread), Edit, Delete (second tap confirms)
+- [ ] "+ Add channel" → Public (re-adds the open channel; "already exists" if it's there), Hashtag (topic → "#topic"), Private (name + passphrase, or Hex key switch → exactly 32 hex chars)
+- [ ] A hashtag / private channel made on L2 talks to the same channel made on L1 or in the phone app
+- [ ] Edit: rename keeps the key (shown at the top); typing a new passphrase changes it
+- [ ] Deleting a channel that was the live share / bot target turns those off; a channel re-added in that slot starts with default notifications / no favourite (also when deleted from the phone app)
+- [ ] L1 (ui-new): Messages > Channels add / edit / delete / mute / pin still work (now through the shared ChannelControl)
+- [ ] L1: deleting a contact from the app still unpins it from the dial and clears its mute / melody (cleanup moved into the Core)
+
 ## Basics after the_mesh moved to PSRAM (`MESH_IN_PSRAM`)
 - [ ] Boots normally, contacts and channels are all there
 - [ ] Messages arrive and send (channel + DM), delivery ticks work

docs/development/ui-core.md

@@ -110,7 +110,7 @@ call the same ones, so e.g. "marking a channel read" has one implementation.
 
 ### 5. Declarative settings schema
 
-`ui-core/SettingsSchema.h` holds three pages -- navigation (trail, live share, arrival alert, units), display & power (brightness, screen off, wake on message, battery shutdown, GPS power saving, time zone) and messages & contacts (DM resends, contact expiry, favourites first). An entry is a one-byte index by default, or a `values` table over a 1/2/4-byte field (seconds, millivolts, an hour offset, `{1, 0}` for a field stored inverted); side effects run through `UiCore` (`applyGpsInterval()`, `host()->applyDisplayPrefs()`). ui-lvgl renders each page; ui-new still uses its own screens. Radio settings are not schema rows (preset list, typed frequency, radio side effects): `ui-core/RadioControl.h` applies them (`applyParams`, `applyTxPower`, `applyApc`, presets = built-ins + user slots) for both ui-new's Settings > Radio and ui-lvgl's Radio screen.
+`ui-core/SettingsSchema.h` holds three pages -- navigation (trail, live share, arrival alert, units), display & power (brightness, screen off, wake on message, battery shutdown, GPS power saving, time zone) and messages & contacts (DM resends, contact expiry, favourites first). An entry is a one-byte index by default, or a `values` table over a 1/2/4-byte field (seconds, millivolts, an hour offset, `{1, 0}` for a field stored inverted); side effects run through `UiCore` (`applyGpsInterval()`, `host()->applyDisplayPrefs()`). ui-lvgl renders each page; ui-new still uses its own screens. Radio settings are not schema rows (preset list, typed frequency, radio side effects): `ui-core/RadioControl.h` applies them (`applyParams`, `applyTxPower`, `applyApc`, presets = built-ins + user slots) for both ui-new's Settings > Radio and ui-lvgl's Radio screen. Channel management is `ui-core/ChannelControl.h` (`chanctl::`): add Public / Hashtag / Private (passphrase or 32-hex key), rename, delete, notifications / favourite / scope, and `onRemoved()` -- the cleanup of every channel-keyed pref, run by `UiCore::onChannelRemoved` whoever deleted the channel (this device or the app); contacts get the same through `UiCore::cleanupContactPrefs`. Favourites dial slots: `ui-core/Favourites.h`.
 
 Replaces the per-item code in `SettingsScreen`: