v0.5.0 — Phase β-4 Media + Advanced Card-Types

Alle 7 Card-Types werden gerendert und können erstellt werden.
image-occlusion mit Touch-Drag-Mask-Editor (kein PencilKit — Server-
Schema erlaubt nur Rechtecke), audio-front mit AVAudioPlayer und
File-Picker.

- MediaUploadResponse-DTO, MaskRegion-Codable mit 0..1-Coordinates
- MaskRegions.parse/encode (1:1-Port aus cards-domain, Sortierung
  nach ID lexikographisch)
- CardFieldsBuilder.imageOcclusion mit stringified-JSON-mask_regions
  + audioFront
- CardsAPI.uploadMedia (Multipart, 25 MiB) + fetchMedia (streamed)
- MediaCache actor mit LRU 200 MB (contentModificationDate-Eviction)
- mediaCache Environment-Key
- RemoteImage + AudioPlayerButton SwiftUI-Views
- CardRenderer: imageOcclusion (Mask-Overlay über RemoteImage) +
  audioFront (AudioPlayerButton + back-Text auf Flip)
- MaskEditorView: Touch-Drag-Rechteck, Label-Edit, Delete
- CardEditorView erweitert: PhotosPicker für Image, fileImporter
  für Audio, Magic-Byte-MIME-Detection
- 6 neue Tests für MaskRegions (30 Total grün)

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

Sources/Features/Editor/MaskEditorView.swift

@@ -0,0 +1,147 @@
+import SwiftUI
+
+#if canImport(UIKit)
+import UIKit
+#endif
+
+/// Mask-Editor: Bild anzeigen, mit Drag-Gesten Rechtecke zeichnen, jede
+/// Region mit Label versehen. Coordinaten 0..1 relativ zur Bild-Größe.
+///
+/// Output binding ist `regions`. Caller serialisiert via `MaskRegions.encode()`.
+struct MaskEditorView: View {
+    let image: PlatformImage
+    @Binding var regions: [MaskRegion]
+
+    @State private var dragStart: CGPoint?
+    @State private var dragEnd: CGPoint?
+    @State private var nextIdCounter: Int = 0
+
+    var body: some View {
+        VStack(alignment: .leading, spacing: 12) {
+            Text("Tippe und ziehe auf das Bild, um eine Maske zu erstellen.")
+                .font(.caption)
+                .foregroundStyle(CardsTheme.mutedForeground)
+
+            imageCanvas
+                .aspectRatio(image.size.width / max(image.size.height, 1), contentMode: .fit)
+                .frame(maxWidth: .infinity)
+                .clipShape(RoundedRectangle(cornerRadius: 8))
+
+            if regions.isEmpty {
+                Text("Noch keine Maske")
+                    .font(.caption)
+                    .foregroundStyle(CardsTheme.mutedForeground)
+            } else {
+                ForEach(regions) { region in
+                    maskRow(region: region)
+                }
+            }
+        }
+    }
+
+    @ViewBuilder
+    private var imageCanvas: some View {
+        GeometryReader { geo in
+            ZStack(alignment: .topLeading) {
+                #if canImport(UIKit)
+                Image(uiImage: image).resizable().aspectRatio(contentMode: .fit)
+                #else
+                Image(nsImage: image).resizable().aspectRatio(contentMode: .fit)
+                #endif
+
+                ForEach(regions) { region in
+                    overlayRect(for: region, in: geo.size)
+                }
+
+                if let dragStart, let dragEnd {
+                    let rect = normalizedRect(from: dragStart, to: dragEnd)
+                    Rectangle()
+                        .stroke(CardsTheme.warning, lineWidth: 2)
+                        .background(Rectangle().fill(CardsTheme.warning.opacity(0.2)))
+                        .frame(width: rect.width, height: rect.height)
+                        .offset(x: rect.minX, y: rect.minY)
+                }
+            }
+            .contentShape(Rectangle())
+            .gesture(
+                DragGesture(minimumDistance: 4)
+                    .onChanged { value in
+                        if dragStart == nil { dragStart = value.startLocation }
+                        dragEnd = value.location
+                    }
+                    .onEnded { value in
+                        commitDrag(start: value.startLocation, end: value.location, in: geo.size)
+                    }
+            )
+        }
+    }
+
+    private func overlayRect(for region: MaskRegion, in size: CGSize) -> some View {
+        Rectangle()
+            .fill(CardsTheme.primary.opacity(0.6))
+            .frame(width: region.w * size.width, height: region.h * size.height)
+            .offset(x: region.x * size.width, y: region.y * size.height)
+            .overlay(
+                Text(region.label?.isEmpty == false ? region.label! : region.id)
+                    .font(.caption2.weight(.bold))
+                    .foregroundStyle(CardsTheme.primaryForeground)
+                    .padding(2)
+                    .offset(x: region.x * size.width + 2, y: region.y * size.height + 2),
+                alignment: .topLeading
+            )
+    }
+
+    private func maskRow(region: MaskRegion) -> some View {
+        HStack(spacing: 8) {
+            Image(systemName: "square.dashed")
+                .foregroundStyle(CardsTheme.primary)
+            TextField("Label (optional)", text: Binding(
+                get: { region.label ?? "" },
+                set: { newValue in updateLabel(for: region.id, to: newValue) }
+            ))
+            .textFieldStyle(.roundedBorder)
+            Button(role: .destructive) {
+                regions.removeAll { $0.id == region.id }
+            } label: {
+                Image(systemName: "trash")
+                    .foregroundStyle(CardsTheme.error)
+            }
+            .buttonStyle(.plain)
+        }
+    }
+
+    private func updateLabel(for id: String, to value: String) {
+        guard let idx = regions.firstIndex(where: { $0.id == id }) else { return }
+        let old = regions[idx]
+        regions[idx] = MaskRegion(id: old.id, x: old.x, y: old.y, w: old.w, h: old.h, label: value)
+    }
+
+    private func normalizedRect(from start: CGPoint, to end: CGPoint) -> CGRect {
+        let x = min(start.x, end.x)
+        let y = min(start.y, end.y)
+        let w = abs(end.x - start.x)
+        let h = abs(end.y - start.y)
+        return CGRect(x: x, y: y, width: w, height: h)
+    }
+
+    private func commitDrag(start: CGPoint, end: CGPoint, in size: CGSize) {
+        defer {
+            dragStart = nil
+            dragEnd = nil
+        }
+        let rect = normalizedRect(from: start, to: end)
+        // Mindestgröße 1% der Bildkante — Tap-Klicks ignorieren
+        guard rect.width > size.width * 0.01, rect.height > size.height * 0.01 else { return }
+        nextIdCounter += 1
+        let id = String(format: "m%03d", nextIdCounter)
+        let normalized = MaskRegion(
+            id: id,
+            x: rect.minX / size.width,
+            y: rect.minY / size.height,
+            w: rect.width / size.width,
+            h: rect.height / size.height,
+            label: nil
+        )
+        regions.append(normalized)
+    }
+}