fix(icon): TestFlight-Validation grün — Icon + CFBundleIconName

Apple Validator hatte drei Fehler geworfen:
  - Missing 120x120 (iPhone) und 152x152 (iPad)
  - Missing Info.plist key CFBundleIconName

Root-Cause: AppIcon.appiconset hatte keinen filename gesetzt → keine
PNG-Variants im Bundle. Plus: bei GENERATE_INFOPLIST_FILE=NO injiziert
Xcode CFBundleIconName nicht automatisch, das muss explizit in die
plist.

Fixes:
- scripts/make-appicon.swift erzeugt 1024×1024-PNG-Platzhalter in
  paper-Theme-Farben (Sienna-Background, dunkles Z, zwei
  Anführungszeichen-Akzente) analog cards-native
- Sources/Resources/Assets.xcassets/AppIcon.appiconset/Contents.json
  verlinkt AppIcon-1024.png für light / dark / tinted (3 Appearances)
- project.yml setzt CFBundleIconName: AppIcon im Info.plist-Root

Archive-Verifikation:
  $ /usr/libexec/PlistBuddy -c "Print :CFBundleIconName" Info.plist
  → AppIcon
  $ ls ZitareNative.app | grep AppIcon
  → AppIcon, AppIcon60x60@2x.png (=120×120), AppIcon76x76@2x~ipad.png
    (=152×152)

Platzhalter — vor produktivem App-Store-Launch durch designtes Icon
ersetzen.

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

scripts/make-appicon.swift

@@ -0,0 +1,89 @@
+#!/usr/bin/env swift
+// Generiert ein 1024×1024-AppIcon-PNG als Platzhalter für Zitare.
+//
+// Design (paper-Variant aus @mana/themes):
+//   - Background: warm Sienna (paper-primary, HSL 18 50% 38%)
+//   - Zwei stilisierte typografische Anführungszeichen oben in
+//     gebrochenem Weiß (paper-background)
+//   - Großes serifenbetontes „Z" zentriert in dunklem Sepia
+//
+// Aufruf:
+//   swift scripts/make-appicon.swift
+//
+// Schreibt nach: Sources/Resources/Assets.xcassets/AppIcon.appiconset/AppIcon-1024.png
+//
+// Dies ist ein Platzhalter — vor App-Store-Submission durch ein
+// designter Icon ersetzen.
+
+import AppKit
+import CoreGraphics
+
+let size = 1024
+let cs = CGColorSpaceCreateDeviceRGB()
+guard let ctx = CGContext(
+    data: nil,
+    width: size, height: size,
+    bitsPerComponent: 8, bytesPerRow: 0,
+    space: cs,
+    bitmapInfo: CGImageAlphaInfo.premultipliedLast.rawValue
+) else {
+    print("CGContext creation failed")
+    exit(1)
+}
+
+// HSL(18, 50%, 38%) — paper-primary, warm Sienna
+let background = CGColor(red: 0.57, green: 0.30, blue: 0.19, alpha: 1)
+ctx.setFillColor(background)
+ctx.fill(CGRect(x: 0, y: 0, width: size, height: size))
+
+// Zwei „Anführungs"-Akzente oben — gebrochenes Weiß (paper-bg-light)
+let accent = CGColor(red: 0.95, green: 0.93, blue: 0.88, alpha: 0.92)
+let quoteFont = NSFont(name: "Georgia-Bold", size: 360)
+    ?? NSFont.boldSystemFont(ofSize: 360)
+let quoteAttrs: [NSAttributedString.Key: Any] = [
+    .font: quoteFont,
+    .foregroundColor: NSColor(cgColor: accent) ?? .white,
+]
+
+// Anführungszeichen links („)
+let leftQuote = NSAttributedString(string: "\u{201E}", attributes: quoteAttrs)
+let leftLine = CTLineCreateWithAttributedString(leftQuote)
+ctx.textPosition = CGPoint(x: 160, y: 520)
+CTLineDraw(leftLine, ctx)
+
+// Anführungszeichen rechts (")
+let rightQuote = NSAttributedString(string: "\u{201C}", attributes: quoteAttrs)
+let rightLine = CTLineCreateWithAttributedString(rightQuote)
+ctx.textPosition = CGPoint(x: 620, y: 520)
+CTLineDraw(rightLine, ctx)
+
+// Großes „Z" mittig — dunkles Sepia, serif
+let zFont = NSFont(name: "Georgia-Bold", size: 640)
+    ?? NSFont.boldSystemFont(ofSize: 640)
+let darkSepia = CGColor(red: 0.22, green: 0.16, blue: 0.12, alpha: 1)
+let zAttrs: [NSAttributedString.Key: Any] = [
+    .font: zFont,
+    .foregroundColor: NSColor(cgColor: darkSepia) ?? .black,
+]
+let zStr = NSAttributedString(string: "Z", attributes: zAttrs)
+let zLine = CTLineCreateWithAttributedString(zStr)
+let zBounds = CTLineGetImageBounds(zLine, ctx)
+let tx = (CGFloat(size) - zBounds.width) / 2 - zBounds.origin.x
+let ty = (CGFloat(size) - zBounds.height) / 2 - zBounds.origin.y - 40
+ctx.textPosition = CGPoint(x: tx, y: ty)
+CTLineDraw(zLine, ctx)
+
+// PNG schreiben
+guard let cgImage = ctx.makeImage() else {
+    print("makeImage failed")
+    exit(1)
+}
+let bitmap = NSBitmapImageRep(cgImage: cgImage)
+guard let data = bitmap.representation(using: .png, properties: [:]) else {
+    print("PNG encoding failed")
+    exit(1)
+}
+
+let target = URL(fileURLWithPath: "Sources/Resources/Assets.xcassets/AppIcon.appiconset/AppIcon-1024.png")
+try data.write(to: target)
+print("Wrote \(target.path) (\(data.count) bytes)")