GiteaPR: native iOS app to manage Gitea pull requests

Multi-repo PR inbox, review (approve/request changes/comment), merge with
gating toggle, read-only diff viewer, and Gitea Actions check status with
one-tap re-run. Ships unsigned via the iMac runner to the SideStore source.

GiteaPR/Networking/KeychainHelper.swift

@@ -0,0 +1,50 @@
+import Foundation
+import Security
+
+/// Minimal Keychain wrapper for the API token and instance URL.
+enum KeychainHelper {
+    private static let service = "com.bueso.giteapr"
+
+    static func set(_ value: String, key: String) {
+        guard let data = value.data(using: .utf8) else { return }
+        let query: [String: Any] = [
+            kSecClass as String: kSecClassGenericPassword,
+            kSecAttrService as String: service,
+            kSecAttrAccount as String: key,
+        ]
+        // Delete any existing item first (upsert semantics).
+        SecItemDelete(query as CFDictionary)
+        var attrs = query
+        attrs[kSecValueData as String] = data
+        attrs[kSecAttrAccessible as String] =
+            kSecAttrAccessibleAfterFirstUnlock
+        SecItemAdd(attrs as CFDictionary, nil)
+    }
+
+    static func get(_ key: String) -> String? {
+        let query: [String: Any] = [
+            kSecClass as String: kSecClassGenericPassword,
+            kSecAttrService as String: service,
+            kSecAttrAccount as String: key,
+            kSecReturnData as String: true,
+            kSecMatchLimit as String: kSecMatchLimitOne,
+        ]
+        var result: AnyObject?
+        let status = SecItemCopyMatching(query as CFDictionary, &result)
+        guard status == errSecSuccess,
+              let data = result as? Data,
+              let string = String(data: data, encoding: .utf8) else {
+            return nil
+        }
+        return string
+    }
+
+    static func delete(_ key: String) {
+        let query: [String: Any] = [
+            kSecClass as String: kSecClassGenericPassword,
+            kSecAttrService as String: service,
+            kSecAttrAccount as String: key,
+        ]
+        SecItemDelete(query as CFDictionary)
+    }
+}