iOS 1.0 RC 2: Update Download and Update All Downloads

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

ios/Stemify/UI/Screens/LibraryScreens.swift

@@ -820,6 +820,12 @@ struct DownloadsScreen: View {
                 SheetAction("Shuffle", icon: "shuffle") { g.playback.playTracks(d.tracks, shuffle: true) },
             ]
             if d.failed > 0 { items.append(SheetAction("Retry Failed Songs", icon: "arrow.clockwise") { g.downloads.retryFailed() }) }
+            items.append(SheetAction("Update Download", icon: "arrow.triangle.2.circlepath") {
+                Task {
+                    let ok = await g.downloads.update(d.group.id)
+                    ui.overlays.hud(ok ? "Download Updated" : "Couldn't reach the server", ok ? "arrow.triangle.2.circlepath" : "exclamationmark.triangle")
+                }
+            })
             items.append(SheetAction("Remove Download", icon: "trash", destructive: true) {
                 ui.overlays.confirm("Remove Download?", "“\(d.group.title)” will no longer be available offline.", "Remove") { g.downloads.removeGroup(d.group.id) }
             })
@@ -851,6 +857,15 @@ struct DownloadsScreen: View {
     private func moreItems(_ all: [DownloadedGroup], _ pinned: String) -> [SheetAction] {
         var a: [SheetAction] = []
         if all.contains(where: { $0.failed > 0 }) { a.append(SheetAction("Retry Failed", icon: "arrow.clockwise") { g.downloads.retryFailed() }) }
+        if !g.downloads.groups.isEmpty {
+            a.append(SheetAction("Update All Downloads", icon: "arrow.triangle.2.circlepath") {
+                Task {
+                    var failed = 0
+                    for id in Array(g.downloads.groups.keys) { if await !g.downloads.update(id) { failed += 1 } }
+                    ui.overlays.hud(failed == 0 ? "Downloads Updated" : "\(failed) couldn't be updated", failed == 0 ? "arrow.triangle.2.circlepath" : "exclamationmark.triangle")
+                }
+            })
+        }
         a.append(SheetAction("Remove All Downloads", icon: "trash", destructive: true) {
             ui.overlays.confirm("Remove All Downloads?", "Frees \(pinned) GB. Songs stay in your library.", "Remove All") {
                 for id in g.downloads.groups.keys { g.downloads.removeGroup(id) }