feat(epg): rework live EPG panel into a horizontal timeline

Replace the vertical EPG list/panel with a single horizontal timeline ribbon
(`app-epg-timeline`) shared across all live surfaces — the M3U player, the
unified live tab, and the Xtream and Stalker layouts. It preloads a multi-day
window and supports scroll, zoom, day navigation, short-programme tiers and
per-state empty/error views; the programme-details dialog is restyled to match
and now shows the channel logo.

Timeline / UI
- Auto-focus the currently-airing programme on channel select — instant
  (`behavior: 'auto'`), centred, and deduped by programme-set identity so the
  30s tick / zoom / re-emits never cause flaky re-jumps.
- Wide-tier cards show a dimmed description preview under the title; title and
  preview clip on whole lines (`flex-shrink: 0` + `-webkit-line-clamp`), never
  mid-line.
- Dynamic bar subtitle: the now-playing / archive programme title instead of a
  static "Timeline" label.
- State-aware toolbar: hide Now + zoom when there is no ribbon, and the date
  stepper when the channel has no EPG on any day (hidden, not disabled).
- Empty-state fills and centres within the panel area instead of a fixed
  min-height that overflowed the compact inline panel and hid the buttons.

EPG current-programme lookup (electron-backend)
- Timezone-aware "airing now" comparison via SQLite `datetime()` (was a lexical
  string compare that broke for offset vs UTC `Z` timestamps).
- Unscoped fallback for resolved candidates whose programmes are tagged with an
  out-of-scope source (multi-source imports sharing XMLTV ids), so the sidebar
  matches the timeline.
- Match channel candidates by the raw (case-sensitive) key as well as `LOWER()`,
  since SQLite `LOWER()`/`COLLATE NOCASE` fold only ASCII — fixes Cyrillic /
  Greek channel names showing "No program information available".
- Overlap-based day membership (`hasProgramsForDateKey`) so a film spanning
  midnight keeps the ribbon on "today" while it airs.

Refactor
- Extract the duplicated channel-list EPG enrichment (progress + side-car map)
  into `channel-list-container/epg-enrichment.util.ts`, shared by the
  all-channels / groups / favorites / recent views; also fixes recent's and
  favorites' unguarded, NaN-prone progress maths.

Tests: ui-epg 75, components 77, electron-backend 432; lint + web build green.

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

apps/web-e2e/src/stalker.e2e.ts

@@ -238,8 +238,7 @@ test('@stalker PWA hides EPG for ITV channel', async ({ page }) => {
     await expect(page.locator('app-web-player-view')).toBeVisible({
         timeout: 20_000,
     });
-    await expect(page.locator('app-epg-list')).toHaveCount(0);
-    await expect(page.locator('app-live-epg-panel')).toHaveCount(0);
+    await expect(page.locator('app-epg-timeline')).toHaveCount(0);
     expect(epgInfoRequests).toHaveLength(0);
     expect(shortEpgRequests).toHaveLength(0);
 });
@@ -292,7 +291,7 @@ test('@stalker radio — stations use the inline audio player without EPG', asyn
     await restoreButton.click();
     await expect(stations.first()).toBeVisible();
 
-    await expect(page.locator('app-epg-list')).toHaveCount(0);
+    await expect(page.locator('app-epg-timeline')).toHaveCount(0);
     expect(epgRequests).toHaveLength(0);
 });
 
@@ -325,11 +324,11 @@ test('@stalker PWA skips bulk EPG across channel switches', async ({
 
     await channels.first().click();
     await expect(channels.first()).toHaveClass(/active/, { timeout: 20_000 });
-    await expect(page.locator('app-epg-list')).toHaveCount(0);
+    await expect(page.locator('app-epg-timeline')).toHaveCount(0);
 
     await channels.nth(1).click();
     await expect(channels.nth(1)).toHaveClass(/active/, { timeout: 20_000 });
-    await expect(page.locator('app-epg-list')).toHaveCount(0);
+    await expect(page.locator('app-epg-timeline')).toHaveCount(0);
     expect(epgInfoRequests).toHaveLength(0);
     expect(shortEpgRequests).toHaveLength(0);
 });