refactor(episode): migrate episode upload to Livewire with real-time CDN verification

Replace the server-rendered episode upload form with a Livewire component,
introducing an interactive admin experience that validates the new episode's
stream path against all configured mirrors before saving. The controller-based
`store` method and its route are removed, and episode creation now flows
through the `AdminEpisodeForm` component with frontend upload handling and
dynamic quality checks.

Key changes:
- Add `AdminEpisodeForm` Livewire component with file uploads, tag handling,
  and debounced stream/base-url validation.
- Extend `CdnPathValidator::validateStream` to accept an episode number so the
  manifest path can point to the specific episode being added.
- Remove the `store` method from `EpisodeController` and its POST route.
- Delete the legacy `createEpisode` method from `EpisodeService`.
- Replace the Blade upload modal with the Livewire view, including progress
  indicators and validation badges.
- Add feature tests for the Livewire component and update unit tests for the
  CDN validator's episode-specific manifest check.

tests/Unit/CdnPathValidatorTest.php

@@ -102,6 +102,24 @@ class CdnPathValidatorTest extends TestCase
         Http::assertSentCount(4);
     }
 
+    public function test_stream_can_target_specific_episode_manifest(): void
+    {
+        Http::fake([
+            'https://dl4k-a.test/*' => Http::response(['valid' => true, 'type' => 'file', 'size' => 1024]),
+            'https://dl4k-b.test/*' => Http::response(['valid' => true, 'type' => 'file', 'size' => 1024]),
+        ]);
+
+        $result = app(CdnPathValidator::class)->validateStream('2026/Title', 1, false, 2);
+
+        $this->assertTrue($result['valid']);
+        $this->assertArrayHasKey('hentai-stream/2026/Title', $result['mirrors']['https://dl4k-a.test']);
+        $this->assertArrayHasKey('hentai-stream/2026/Title/E02/720/manifest.mpd', $result['mirrors']['https://dl4k-a.test']);
+        $this->assertArrayHasKey('hentai-stream/2026/Title/E02/720/manifest.mpd', $result['mirrors']['https://dl4k-b.test']);
+        $this->assertArrayNotHasKey('hentai-stream/2026/Title/E01/720/manifest.mpd', $result['mirrors']['https://dl4k-a.test']);
+        $this->assertArrayNotHasKey('hentai-stream/2026/Title/E01/720/manifest.mpd', $result['mirrors']['https://dl4k-b.test']);
+        $this->assertSame(4, count(Http::recorded()));
+    }
+
     public function test_results_are_cached_for_short_period(): void
     {
         Http::fake([