feat(epg): add vertical list view for the live EPG panel

Add an EPG list view — a vertical, single-day programme list — as an
alternative rendering of the live EPG panel, selectable via a new
Settings → EPG → "Guide view" toggle (epgViewMode: 'timeline' | 'list',
default 'timeline' so existing users see no change).

- New EpgListViewComponent (app-epg-list-view) mirrors
  EpgTimelineComponent's input/output contract 1:1, so all four live
  hosts (M3U player, unified live tab, Xtream, Stalker) swap the panel
  with a plain @if and identical bindings.
- Reuses the shared view-agnostic EPG modules (classifyTimelineWhen,
  hasProgramsForDateKey, epg-archive.util catch-up gating,
  epg-summary.util collapsed-summary maths, epg-date helpers,
  EpgProgrammeDialogService, app-epg-timeline-empty-state) — no
  duplicated logic.
- Rows show time range, title, optional description, live progress on
  the on-air row, catch-up "Watch" on past rows when archive playback
  is available, and a details dialog; keyboard activation guards
  nested buttons (target === currentTarget).
- Auto-focuses the on-air row on channel select, restores it across
  collapse/expand remounts, and shows a sticky in-flow "On now" strip
  (never overlaying rows) when the current programme is scrolled away;
  all scroll maths is rect-based relative to the scroller.
- List mode raises only the inline panel height via an epg--list
  modifier (--epg-inline-height clamp); timeline and collapsed heights
  are unchanged.
- Setting flows end-to-end (Settings interface → DEFAULT_SETTINGS →
  SettingsStore/StorageMap → segmented control in the EPG section);
  Electron-only UI, PWA stays on the timeline default. i18n keys added
  to all 18 locales.
- Tests: new component/row/utils/scroll-controller specs, settings
  persistence spec, swap tests in all four host specs, and Electron
  E2E for the settings round-trip and the rendered list view. Docs
  updated (m3u-playlist-module.md).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

apps/electron-backend-e2e/src/settings.e2e.ts

@@ -231,6 +231,38 @@ test.describe('Electron Settings', () => {
         }
     });
 
+    test('@settings @persistence @electron persists the EPG view mode across app restart', async ({
+        dataDir,
+    }) => {
+        const firstLaunch = await launchElectronApp(dataDir);
+
+        try {
+            await openSettings(firstLaunch.mainWindow);
+            const listToggle = firstLaunch.mainWindow.locator(
+                '[data-test-id="epg-view-mode-list"]'
+            );
+            await expect(listToggle).toBeVisible();
+            await listToggle.click();
+            await expect(listToggle).toHaveAttribute('aria-checked', 'true');
+            await saveSettings(firstLaunch.mainWindow);
+        } finally {
+            await closeElectronApp(firstLaunch);
+        }
+
+        const secondLaunch = await launchElectronApp(dataDir);
+
+        try {
+            await openSettings(secondLaunch.mainWindow);
+            await expect(
+                secondLaunch.mainWindow.locator(
+                    '[data-test-id="epg-view-mode-list"]'
+                )
+            ).toHaveAttribute('aria-checked', 'true');
+        } finally {
+            await closeElectronApp(secondLaunch);
+        }
+    });
+
     test('@settings @electron starts on sources when dashboard is disabled', async ({ dataDir }) => {
         const firstLaunch = await launchElectronApp(dataDir);