Add Gitea CI workflow with IPA distribution

On every push to swift/master: compile-checks against the simulator
(no signing required) then builds a development IPA and deploys it to
the shared OTA server at krishnas-mac-studio.tail37d544.ts.net:8443.

Modelled on 1ai's ci.yaml — runs on the local macos act runner so the
keychain is live and automatic signing works without any cert setup.

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

scripts/ipa-server/build-and-deploy.sh

@@ -34,9 +34,13 @@ elif [ -n "$1" ] && [ "$1" != "$CURRENT_BRANCH" ]; then
     COMMIT=$(git rev-parse --short HEAD)
     echo "📌 Building commit: $COMMIT on $1"
 else
-    echo "⬇️  Pulling latest $CURRENT_BRANCH..."
-    git pull origin "$CURRENT_BRANCH"
     COMMIT=$(git rev-parse --short HEAD)
+    if git ls-remote --exit-code origin "$CURRENT_BRANCH" &>/dev/null; then
+        echo "⬇️  Pulling latest $CURRENT_BRANCH..."
+        git pull origin "$CURRENT_BRANCH"
+    else
+        echo "⚠️  No remote for $CURRENT_BRANCH — building local HEAD"
+    fi
     echo "📌 Building commit: $COMMIT on $CURRENT_BRANCH"
 fi