fix: enrich player track info from API + share button feedback

PlayerTrackInfoView auto-fetches full release data when current track
is missing audio/lastfm fields (e.g. after device transfer). Share
button turns green with checkmark for 1.5s after copying URL.

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

furumi_macos/ContentView.swift

@@ -36,6 +36,7 @@ struct ContentView: View {
     @State private var showingQueue = false
     @State private var showingDevices = false
     @State private var remoteSeekOverride: Double? = nil  // optimistic seek for client mode
+    @State private var shareCopied = false
 
     // ViewModels bound to session (optional)
     @State private var globalVM: GlobalArtistsViewModel?
@@ -560,9 +561,11 @@ struct ContentView: View {
                     .disabled(player.currentTrack == nil)
 
                     Button(action: shareCurrentTrack) {
-                        Image(systemName: "square.and.arrow.up").font(.system(size: 14))
+                        Image(systemName: shareCopied ? "checkmark" : "square.and.arrow.up")
+                            .font(.system(size: 14))
                     }
-                    .buttonStyle(.plain).foregroundColor(.secondary)
+                    .buttonStyle(.plain)
+                    .foregroundColor(shareCopied ? .green : .secondary)
                     .disabled(player.currentTrack == nil)
 
                     Button(action: { showingTrackInfo.toggle() }) {
@@ -572,7 +575,7 @@ struct ContentView: View {
                     .disabled(player.currentTrack == nil)
                     .popover(isPresented: $showingTrackInfo, arrowEdge: .bottom) {
                         if let track = player.currentTrack {
-                            TrackInfoView(track: track)
+                            PlayerTrackInfoView(track: track, service: authManager.catalogService)
                         }
                     }
 
@@ -706,6 +709,11 @@ struct ContentView: View {
         let url = "\(baseUrl.trimmingCharacters(in: CharacterSet(charactersIn: "/")))/share/track/\(track.id)"
         NSPasteboard.general.clearContents()
         NSPasteboard.general.setString(url, forType: .string)
+        withAnimation(.easeIn(duration: 0.1)) { shareCopied = true }
+        Task {
+            try? await Task.sleep(nanoseconds: 1_500_000_000)
+            withAnimation(.easeOut(duration: 0.4)) { shareCopied = false }
+        }
     }
 }
 

furumi_macos/TrackInfoView.swift

@@ -5,6 +5,24 @@
 
 import SwiftUI
 
+/// Wrapper used by the player bar — enriches track data from the API if fields are missing
+struct PlayerTrackInfoView: View {
+    let track: TrackCard
+    let service: CatalogService?
+
+    @State private var enriched: TrackCard?
+
+    var body: some View {
+        TrackInfoView(track: enriched ?? track)
+            .task(id: track.id) {
+                guard track.audioFormat == nil, track.releaseId > 0, let service else { return }
+                guard let detail = try? await service.releaseDetail(id: track.releaseId),
+                      let full = detail.tracks.first(where: { $0.id == track.id }) else { return }
+                enriched = full
+            }
+    }
+}
+
 struct TrackInfoView: View {
     let track: TrackCard