refactor(ui): Lucide migration unit 2 — Icons.* -> LucideIcons.* sweep (#60)

Mechanical sweep across 30 files: every Material Icons.* replaced with
the signed-off Lucide equivalent + a flutter_lucide import per file.
Zero Material Icons.* remain in lib/; no unused imports.

Judgment-call mappings: album->disc_3, library_music->library_big,
playlist_play->list_video, graphic_eq->audio_lines,
system_update->download, restore->archive_restore,
download_done->circle_check_big.

track_actions_sheet like menu row: collapsed `liked ? favorite :
favorite_border` to a single LucideIcons.heart (the row's Like/Unlike
text label conveys state). Icon-only LikeButton + the notification keep
the filled-vs-outline shape per the design decision.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

flutter_client/lib/library/album_detail_screen.dart

@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import 'package:flutter_lucide/flutter_lucide.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 
 import '../api/endpoints/likes.dart';
@@ -115,7 +116,7 @@ class AlbumDetailScreen extends ConsumerWidget {
                     width: 48, height: 48,
                     decoration: BoxDecoration(color: fs.accent, shape: BoxShape.circle),
                     child: IconButton(
-                      icon: Icon(Icons.play_arrow, color: fs.parchment),
+                      icon: Icon(LucideIcons.play, color: fs.parchment),
                       onPressed: () => ref.read(playerActionsProvider).playTracks(r.tracks),
                     ),
                   ),

flutter_client/lib/library/artist_detail_screen.dart

@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import 'package:flutter_lucide/flutter_lucide.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:go_router/go_router.dart';
 
@@ -90,7 +91,7 @@ class ArtistDetailScreen extends ConsumerWidget {
                 width: 48, height: 48,
                 decoration: BoxDecoration(color: fs.accent, shape: BoxShape.circle),
                 child: IconButton(
-                  icon: Icon(Icons.play_arrow, color: fs.parchment),
+                  icon: Icon(LucideIcons.play, color: fs.parchment),
                   onPressed: () async {
                     try {
                       final tracks =

flutter_client/lib/library/home_screen.dart

@@ -1,5 +1,6 @@
 import 'package:dio/dio.dart';
 import 'package:flutter/material.dart';
+import 'package:flutter_lucide/flutter_lucide.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:go_router/go_router.dart';
 
@@ -245,12 +246,12 @@ class _PlaylistsSection extends StatelessWidget {
       if (offline) ...const [
         _OfflinePoolCard(
           label: 'Recently played',
-          icon: Icons.history,
+          icon: LucideIcons.history,
           kind: _OfflinePoolKind.recentlyPlayed,
         ),
         _OfflinePoolCard(
           label: 'Liked',
-          icon: Icons.favorite,
+          icon: LucideIcons.heart,
           kind: _OfflinePoolKind.liked,
         ),
       ],

flutter_client/lib/library/library_screen.dart

@@ -2,6 +2,7 @@ import 'dart:convert';
 
 import 'package:drift/drift.dart' as drift;
 import 'package:flutter/material.dart';
+import 'package:flutter_lucide/flutter_lucide.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:go_router/go_router.dart';
 
@@ -382,7 +383,7 @@ class _LibraryScreenState extends ConsumerState<LibraryScreen>
           IconButton(
             key: const Key('shuffle_all_button'),
             tooltip: 'Shuffle all',
-            icon: Icon(Icons.shuffle, color: fs.parchment),
+            icon: Icon(LucideIcons.shuffle, color: fs.parchment),
             onPressed: () async {
               final messenger = ScaffoldMessenger.of(context);
               final refs = await ref.read(shuffleSourceProvider).tracks();
@@ -866,7 +867,7 @@ class _QuarantineTile extends ConsumerWidget {
         ),
         IconButton(
           tooltip: 'Unhide',
-          icon: Icon(Icons.restore, color: fs.ash, size: 20),
+          icon: Icon(LucideIcons.archive_restore, color: fs.ash, size: 20),
           onPressed: () async {
             try {
               await ref.read(myQuarantineProvider.notifier).unflag(row.trackId);

flutter_client/lib/library/widgets/cached_indicator.dart

@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import 'package:flutter_lucide/flutter_lucide.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 
 import '../../cache/audio_cache_manager.dart';
@@ -21,7 +22,7 @@ class CachedIndicator extends ConsumerWidget {
         if (snap.data != true) return const SizedBox.shrink();
         return Padding(
           padding: const EdgeInsets.only(left: 4),
-          child: Icon(Icons.download_done, size: 14, color: fs.accent),
+          child: Icon(LucideIcons.circle_check_big, size: 14, color: fs.accent),
         );
       },
     );

flutter_client/lib/library/widgets/play_circle_button.dart

@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import 'package:flutter_lucide/flutter_lucide.dart';
 
 import '../../theme/theme_extension.dart';
 
@@ -85,7 +86,7 @@ class _PlayCircleButtonState extends State<PlayCircleButton> {
                   ),
                 )
               : Icon(
-                  Icons.play_arrow,
+                  LucideIcons.play,
                   color: fs.parchment,
                   size: iconSize,
                 ),