feat: persist local configuration and device identity (#3)

Store receiver and identity together in Keychain, with versioned tracking
preferences, explicit authorization retry and stable Settings focus.
Adopt free Apple Development locally and credential-free ad hoc CI.
Run configuration and focus tests through both CI toolchains.

Final decisions: https://github.com/jayanezj/traccar-client-macos/issues/3#issuecomment-6396087703

Configuration/Signing.local.xcconfig.example

@@ -0,0 +1,5 @@
+// Copy to Signing.local.xcconfig (ignored by Git) and use your own Personal Team ID.
+DEVELOPMENT_TEAM = YOUR_TEAM_ID
+
+// Optional: use a certificate's SHA-1 identifier if Apple Development is ambiguous.
+// CODE_SIGN_IDENTITY = YOUR_CERTIFICATE_SHA1