perf(playlist): make the playlist import and shared UI components OnPush

Plan item C6 step 3 for libs/playlist (import/feature and shared/ui): the
twelve Eager components switch to OnPush. Two of them rendered plain fields
written after an await, outside any template event, which only an Eager
check on the next zone tick picked up:

- playlist-item's portal status dot (PWA, after the async portal check)
  now reads a signal;
- playlist-info's playlist is backed by a signal behind its existing
  getter/setter name, so the EPG source list follows removals and file
  picks that land after awaited cleanup and dialogs.

A regression test for each fails on OnPush with the plain field and passes
with the signal. The Stalker import's post-await patchValue needs no change
(see the zoneless checklist). The m3u feature-player components stay Eager
for the playback PR.

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

docs/architecture/zoneless-migration.md

@@ -124,20 +124,20 @@ files that still contain `ChangeDetectionStrategy.Eager`.
 
 ### libs/playlist (14)
 
-- [ ] `libs/playlist/import/feature/src/lib/add-playlist-dialog/add-playlist-dialog.component.ts`
-- [ ] `libs/playlist/import/feature/src/lib/auto-import/auto-import.component.ts`
-- [ ] `libs/playlist/import/feature/src/lib/file-upload/file-upload.component.ts`
-- [ ] `libs/playlist/import/feature/src/lib/stalker-portal-import/stalker-portal-import.component.ts`
-- [ ] `libs/playlist/import/feature/src/lib/text-import/text-import.component.ts`
-- [ ] `libs/playlist/import/feature/src/lib/url-upload/url-upload.component.ts`
-- [ ] `libs/playlist/import/feature/src/lib/xtream-code-import/xtream-code-import.component.ts`
+- [x] `libs/playlist/import/feature/src/lib/add-playlist-dialog/add-playlist-dialog.component.ts`
+- [x] `libs/playlist/import/feature/src/lib/auto-import/auto-import.component.ts`
+- [x] `libs/playlist/import/feature/src/lib/file-upload/file-upload.component.ts`
+- [x] `libs/playlist/import/feature/src/lib/stalker-portal-import/stalker-portal-import.component.ts`
+- [x] `libs/playlist/import/feature/src/lib/text-import/text-import.component.ts`
+- [x] `libs/playlist/import/feature/src/lib/url-upload/url-upload.component.ts`
+- [x] `libs/playlist/import/feature/src/lib/xtream-code-import/xtream-code-import.component.ts`
 - [ ] `libs/playlist/m3u/feature-player/src/lib/m3u-vod-detail/m3u-vod-detail.component.ts`
 - [ ] `libs/playlist/m3u/feature-player/src/lib/video-player/video-player.component.ts`
-- [ ] `libs/playlist/shared/ui/src/lib/recent-playlists/empty-state/empty-state.component.ts`
-- [ ] `libs/playlist/shared/ui/src/lib/recent-playlists/playlist-info/playlist-info.component.ts`
-- [ ] `libs/playlist/shared/ui/src/lib/recent-playlists/playlist-item/playlist-item.component.ts`
-- [ ] `libs/playlist/shared/ui/src/lib/source-health/source-cleanup-dialog.component.ts`
-- [ ] `libs/playlist/shared/ui/src/lib/source-health/source-health-indicator.component.ts`
+- [x] `libs/playlist/shared/ui/src/lib/recent-playlists/empty-state/empty-state.component.ts`
+- [x] `libs/playlist/shared/ui/src/lib/recent-playlists/playlist-info/playlist-info.component.ts`
+- [x] `libs/playlist/shared/ui/src/lib/recent-playlists/playlist-item/playlist-item.component.ts`
+- [x] `libs/playlist/shared/ui/src/lib/source-health/source-cleanup-dialog.component.ts`
+- [x] `libs/playlist/shared/ui/src/lib/source-health/source-health-indicator.component.ts`
 
 `libs/playlist/m3u/feature-player` (2) goes with the playback PR.
 
@@ -167,9 +167,9 @@ the field a signal (or a `computed`), or writes it through one.
 | --- | --- | --- | --- |
 | [ ] | `libs/playlist/m3u/feature-player/src/lib/video-player/video-player.component.ts` `onChannelNumberInput`/`clearChannelNumberInput` | 2 s `window.setTimeout` hides the channel-number overlay through plain `showChannelNumberOverlay`/`channelNumberInput` | playback |
 | [ ] | same file, `applySettings` and the settings `effect()` | IndexedDB `storage.get(...).subscribe` and an effect assign plain `playerSettings`, which picks the player in the template | playback |
-| [ ] | `libs/playlist/shared/ui/src/lib/recent-playlists/playlist-item/playlist-item.component.ts` `checkPortalStatus` | plain `portalStatus` assigned after `await` in `ngOnInit` (PWA only: skipped when source health is supported) | playlist |
-| [ ] | `libs/playlist/shared/ui/src/lib/recent-playlists/playlist-info/playlist-info.component.ts` (EPG clear and EPG file pick handlers) | plain `playlist` reassigned after `await` | playlist |
-| [ ] | `libs/playlist/import/feature/src/lib/stalker-portal-import/stalker-portal-import.component.ts` (device-id derivation) | `form.patchValue` after `await`; template getters read `control.value`, which is not signal-backed | playlist |
+| [x] | `libs/playlist/shared/ui/src/lib/recent-playlists/playlist-item/playlist-item.component.ts` `checkPortalStatus` | plain `portalStatus` assigned after `await` in `ngOnInit` (PWA only: skipped when source health is supported) | playlist |
+| [x] | `libs/playlist/shared/ui/src/lib/recent-playlists/playlist-info/playlist-info.component.ts` (EPG clear and EPG file pick handlers) | plain `playlist` reassigned after `await` | playlist |
+| [x] | `libs/playlist/import/feature/src/lib/stalker-portal-import/stalker-portal-import.component.ts` (device-id derivation) | `form.patchValue` after `await`; no fix needed: while derivation is on `hasManualDeviceIds` is false whatever the IDs are, the controls write their own DOM values, and typing goes through value-accessor listeners that mark the view | playlist |
 | [ ] | `libs/portal/stalker/feature/src/lib/stalker-live-stream-layout/stalker-live-stream-layout.component.ts` (favorites load) | `favorites` Map filled in a `subscribe` without `markForCheck`; the component is OnPush already, so this is a latent bug today | portal |
 | [ ] | `libs/portal/xtream/feature/src/lib/portal-channels-list/portal-channels-list.component.ts` (favorites load) | same pattern; the neighbouring `favoriteMarks.changes$` handler does call `markForCheck` | portal |
 | [ ] | same file, programme dialog `afterClosed` | deletes from `epgPrograms`/`currentProgramsProgress` after `await` without marking | portal |