chore(xcode): add XcodeGen scaffold for device deployment

Adds project.yml (XcodeGen spec), Info.plist, entitlements, and
placeholder asset catalog so the project can be built in Xcode
and deployed to iPhone 14 via USB or wireless pairing.

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

project.yml

@@ -0,0 +1,50 @@
+name: SilverApple
+
+options:
+  bundleIdPrefix: uk.silverlabs
+  deploymentTarget:
+    iOS: "16.0"
+  xcodeVersion: "15.0"
+  createIntermediateGroups: true
+  groupSortPosition: top
+
+settings:
+  base:
+    SWIFT_VERSION: "5.9"
+    DEVELOPMENT_TEAM: ""  # Fill in your Apple Developer Team ID before building
+    CODE_SIGN_STYLE: Automatic
+    ENABLE_BITCODE: false
+
+targets:
+  SilverApple:
+    type: application
+    platform: iOS
+    deploymentTarget: "16.0"
+    sources:
+      - path: SilverApple
+    settings:
+      base:
+        PRODUCT_BUNDLE_IDENTIFIER: uk.silverlabs.silverapple
+        INFOPLIST_FILE: SilverApple/Info.plist
+        CODE_SIGN_ENTITLEMENTS: SilverApple/SilverApple.entitlements
+        ASSETCATALOG_COMPILER_APPICON_NAME: AppIcon
+        TARGETED_DEVICE_FAMILY: "1"  # iPhone only
+    dependencies:
+      - framework: AuthenticationServices.framework
+        embed: false
+      - framework: SafariServices.framework
+        embed: false
+      - framework: Security.framework
+        embed: false
+
+  SilverAppleTests:
+    type: bundle.unit-test
+    platform: iOS
+    deploymentTarget: "16.0"
+    sources:
+      - path: SilverAppleTests
+    settings:
+      base:
+        PRODUCT_BUNDLE_IDENTIFIER: uk.silverlabs.silverapple.tests
+    dependencies:
+      - target: SilverApple