fix(images): decode cast cards at the square grid-cell budget

close #1591

lib/utils/media_image_helper.dart

@@ -19,8 +19,8 @@ enum ImageType {
   thumb, // 16:9 episode thumbnails
   logo, // Variable ratio clear logos
   heroLogo, // Large hero clear logos
-  avatar, // Square-ish user avatars
-  square, // 1:1 music artwork (albums, artists, tracks)
+  avatar, // Small square-ish avatars (user profiles, inline person headers)
+  square, // 1:1 grid-cell artwork (albums, artists, tracks, cast cards)
 }
 
 /// Backend-neutral image URL helper.

lib/widgets/cast_member_strip.dart

@@ -214,7 +214,7 @@ class CastMemberStripState extends State<CastMemberStrip> {
                                 width: imageSize,
                                 height: imageSize,
                                 fit: BoxFit.cover,
-                                imageType: ImageType.avatar,
+                                imageType: ImageType.square,
                                 fallbackIcon: Symbols.person_rounded,
                               ),
                             ),

lib/widgets/tv_browse_rail.dart

@@ -1564,7 +1564,7 @@ class TvBrowseRailState extends State<TvBrowseRail> {
                   width: cardWidth,
                   height: imageSize,
                   fit: BoxFit.cover,
-                  imageType: ImageType.avatar,
+                  imageType: ImageType.square,
                   fallbackIcon: Symbols.person_rounded,
                 ),
                 RasterizedGradient(
@@ -1631,7 +1631,7 @@ class TvBrowseRailState extends State<TvBrowseRail> {
                   width: imageSize,
                   height: imageSize,
                   fit: BoxFit.cover,
-                  imageType: ImageType.avatar,
+                  imageType: ImageType.square,
                   fallbackIcon: Symbols.person_rounded,
                 ),
               ),

test/utils/media_image_helper_test.dart

@@ -158,6 +158,21 @@ void main() {
       );
     });
 
+    test('square keeps a grid-cell decode budget while avatar stays small', () {
+      DevicePerformance.debugReset(autoReduced: false, override: VisualEffectsSetting.auto);
+
+      // Cast cards fill poster-width grid cells (issue #1591): a retina cell
+      // needs well over the avatar cap, so they use the square budget.
+      expect(
+        MediaImageHelper.getMemCacheDimensions(displayWidth: 4000, displayHeight: 4000, imageType: ImageType.square),
+        (720, 720),
+      );
+      expect(
+        MediaImageHelper.getMemCacheDimensions(displayWidth: 4000, displayHeight: 4000, imageType: ImageType.avatar),
+        (300, 300),
+      );
+    });
+
     test('card artwork follows square, wide, and poster media shapes', () {
       for (final kind in [MediaKind.artist, MediaKind.album, MediaKind.track]) {
         expect(

test/widgets/cast_member_strip_test.dart

@@ -3,8 +3,10 @@ import 'package:flutter/services.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:plezy/services/settings_service.dart';
 import 'package:plezy/theme/mono_theme.dart';
+import 'package:plezy/utils/media_image_helper.dart';
 import 'package:plezy/utils/platform_detector.dart';
 import 'package:plezy/widgets/cast_member_strip.dart';
+import 'package:plezy/widgets/optimized_media_image.dart';
 
 import '../test_helpers/prefs.dart';
 
@@ -68,6 +70,23 @@ void main() {
     expect(navigatedDown, 1);
   });
 
+  testWidgets('renders member images with the square grid-cell decode budget', (tester) async {
+    // Cast cards are poster-cell sized; the small avatar budget decodes them
+    // below retina resolution and blurs them (issue #1591).
+    await tester.pumpWidget(
+      MaterialApp(
+        theme: monoTheme(dark: true),
+        home: Scaffold(body: CastMemberStrip(members: _members)),
+      ),
+    );
+
+    final images = tester.widgetList<OptimizedMediaImage>(find.byType(OptimizedMediaImage));
+    expect(images, hasLength(_members.length));
+    for (final image in images) {
+      expect(image.imageType, ImageType.square);
+    }
+  });
+
   testWidgets('clamps its focus index when the member list changes', (tester) async {
     final key = GlobalKey<CastMemberStripState>();
     var members = _members;