Implement public ShareViewerScreen with Android deep-link intent-filter (9b)

- New ShareViewerScreen (/share/:token): unauthenticated share-viewer that
  fetches share metadata via publicApiClientProvider, renders filename, type,
  duration, thumbnail, and a Play button routing to the video/audio player.
- New publicApiClientProvider: bare Dio client (no auth interceptors) for the
  public share endpoint; shares kPlayerBaseUrl with the authenticated client.
- AndroidManifest: http + https deep-link intent-filters for /share/.* so
  Android routes share URLs directly into the app (App Links / autoVerify).
- router.dart: /share/:token bypasses the authentication redirect; guard uses
  AppRoutes.shareViewerPrefix constant instead of a raw '/share/' string (DIP).
- app_routes.dart: shareViewer route constant, shareViewerPrefix, shareViewerPath helper.
- error_mappers.dart: shareViewerErrorMessage — 404 invalid/revoked, 410 expired.
- player_api_client.dart: baseUrl getter encapsulates rawDio.options.baseUrl so
  screens never access transport internals directly (ISP, DIP).
- Review fixes: OCP icon map in _FallbackThumbnail, LSP explicit baseUrl
  overrides in test fakes, DIP shareViewerPrefix constant.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

1 files changed, 30 insertions, 0 deletions

diff --git a/player-android/android/app/src/main/AndroidManifest.xml b/player-android/android/app/src/main/AndroidManifest.xml
index 602051c..3276ad7 100644
--- a/player-android/android/app/src/main/AndroidManifest.xml
+++ b/player-android/android/app/src/main/AndroidManifest.xml
@@ -29,6 +29,36 @@
                 <action android:name="android.intent.action.MAIN" />
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
+            <!-- Deep-link intent-filter for public share URLs.
+                 When a user opens a link of the form
+                   https://<PLAYER_HOST>/share/<token>
+                 Android routes the intent to this activity and go_router
+                 navigates to the ShareViewerScreen (/share/:token).
+                 Replace PLAYER_HOST with the real server hostname (e.g.
+                 player.example.com) for production deployments; the wildcard
+                 host below accepts any host for development flexibility.
+                 android:autoVerify="true" enables App Links (verified deep
+                 links) once an assetlinks.json file is served at the host;
+                 without verification the OS shows the disambiguation dialog.
+                 Both http and https schemes are declared so links work with
+                 self-signed or non-TLS development servers as well as
+                 production HTTPS deployments. -->
+            <intent-filter android:autoVerify="true">
+                <action android:name="android.intent.action.VIEW" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+                <data android:scheme="https"
+                      android:host="PLAYER_HOST"
+                      android:pathPattern="/share/.*" />
+            </intent-filter>
+            <intent-filter android:autoVerify="true">
+                <action android:name="android.intent.action.VIEW" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+                <data android:scheme="http"
+                      android:host="PLAYER_HOST"
+                      android:pathPattern="/share/.*" />
+            </intent-filter>
         </activity>
         <meta-data
             android:name="flutterEmbedding"