build(release): Android signing, iOS privacy manifest, store assets (Phase 7)

- Android: release keystore signing wired via gitignored key.properties (falls
  back to debug when absent). Verified: signed AAB built (signer CN=Block Seasons).
- iOS: app PrivacyInfo.xcprivacy (ATT tracking flag, device-id/usage data types,
  UserDefaults+FileTimestamp required-reason APIs) registered in the Runner target.
- Store: app-ads.txt (pub-5605900229781491), EN/KO listing copy, owner submission
  guide (privacy labels, app-ads hosting, upload/submit steps).
Secrets (keystore, key.properties) are gitignored — owner backs them up.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

ios/Runner/PrivacyInfo.xcprivacy

@@ -0,0 +1,64 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<!-- The app uses data for tracking (personalized ads, gated by the ATT
+	     prompt). Google's AdMob/Firebase SDKs ship their own privacy manifests
+	     that declare the tracking domains; this app-level manifest declares the
+	     app's own collected data and required-reason API usage. -->
+	<key>NSPrivacyTracking</key>
+	<true/>
+	<key>NSPrivacyTrackingDomains</key>
+	<array/>
+	<key>NSPrivacyCollectedDataTypes</key>
+	<array>
+		<dict>
+			<key>NSPrivacyCollectedDataType</key>
+			<string>NSPrivacyCollectedDataTypeDeviceID</string>
+			<key>NSPrivacyCollectedDataTypeLinked</key>
+			<false/>
+			<key>NSPrivacyCollectedDataTypeTracking</key>
+			<true/>
+			<key>NSPrivacyCollectedDataTypePurposes</key>
+			<array>
+				<string>NSPrivacyCollectedDataTypePurposeThirdPartyAdvertising</string>
+			</array>
+		</dict>
+		<dict>
+			<key>NSPrivacyCollectedDataType</key>
+			<string>NSPrivacyCollectedDataTypeProductInteraction</string>
+			<key>NSPrivacyCollectedDataTypeLinked</key>
+			<false/>
+			<key>NSPrivacyCollectedDataTypeTracking</key>
+			<false/>
+			<key>NSPrivacyCollectedDataTypePurposes</key>
+			<array>
+				<string>NSPrivacyCollectedDataTypePurposeAnalytics</string>
+				<string>NSPrivacyCollectedDataTypePurposeAppFunctionality</string>
+			</array>
+		</dict>
+	</array>
+	<key>NSPrivacyAccessedAPITypes</key>
+	<array>
+		<dict>
+			<!-- shared_preferences reads/writes the app's own UserDefaults. -->
+			<key>NSPrivacyAccessedAPIType</key>
+			<string>NSPrivacyAccessedAPICategoryUserDefaults</string>
+			<key>NSPrivacyAccessedAPITypeReasons</key>
+			<array>
+				<string>CA92.1</string>
+			</array>
+		</dict>
+		<dict>
+			<!-- Season content cache reads/writes + stats file timestamps in the
+			     app container (path_provider / ContentDownloader). -->
+			<key>NSPrivacyAccessedAPIType</key>
+			<string>NSPrivacyAccessedAPICategoryFileTimestamp</string>
+			<key>NSPrivacyAccessedAPITypeReasons</key>
+			<array>
+				<string>C617.1</string>
+			</array>
+		</dict>
+	</array>
+</dict>
+</plist>