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

scripts/signing-options.sh

@@ -0,0 +1,15 @@
+#!/bin/bash
+# Shared by build/test/verification scripts; development never falls back to ad hoc.
+signing_mode="${TRACCAR_SIGNING_MODE:-development}"
+case "$signing_mode" in
+    development)
+        signing_options=("CODE_SIGN_STYLE=Manual")
+        ;;
+    adhoc)
+        signing_options=("CODE_SIGN_STYLE=Manual" "CODE_SIGN_IDENTITY=-" "DEVELOPMENT_TEAM=")
+        ;;
+    *)
+        echo "TRACCAR_SIGNING_MODE must be development or adhoc." >&2
+        exit 2
+        ;;
+esac