Add macOS compatibility CI: unit tests + smoke test on macos-14/15 (#769)

* Add macOS compatibility CI: unit tests + smoke test on macos-14/15

New workflow runs on GitHub-hosted macos-14 and macos-15 runners
(matrix strategy). Each run: unit tests via cmux-unit scheme, then
a smoke test that builds the app, launches it, sends a command via
the socket, and verifies it stays alive for 15 seconds.

* Select latest Xcode on runner (fix macos-14 Swift tools version)

macos-14 runners default to Xcode 15.4, but sentry-cocoa needs
Swift tools version 6.0 (Xcode 16+). Pick the latest Xcode_*.app
instead of the default symlink.

* Launch app binary directly in smoke test for better CI compatibility

Using `open` can fail silently on CI runners. Launch the binary
directly with env vars set, capture stdout/stderr, and add process
health checks with diagnostic output (debug log tail, crash reports)
on failure.

scripts/smoke-test-ci.sh

@@ -0,0 +1,144 @@
+#!/usr/bin/env bash
+# Smoke test for CI: launch the app, send a command, verify it stays alive for 15 seconds.
+set -euo pipefail
+
+SOCKET_PATH="/tmp/cmux-debug.sock"
+STABILITY_WAIT=15
+
+echo "=== Smoke Test ==="
+
+# --- Find the built app ---
+APP=$(find ~/Library/Developer/Xcode/DerivedData -path "*/Build/Products/Debug/cmux DEV.app" -print -quit 2>/dev/null || true)
+if [ -z "$APP" ]; then
+  echo "ERROR: Built app not found in DerivedData"
+  exit 1
+fi
+echo "App: $APP"
+BINARY="$APP/Contents/MacOS/cmux DEV"
+if [ ! -x "$BINARY" ]; then
+  echo "ERROR: App binary not found or not executable: $BINARY"
+  exit 1
+fi
+
+# --- Clean up stale socket and any existing instances ---
+rm -f "$SOCKET_PATH"
+pkill -x "cmux DEV" 2>/dev/null || true
+sleep 1
+
+# --- Launch the app directly (not via `open`, which can silently fail on CI) ---
+echo "Launching app..."
+CMUX_SOCKET_MODE=allowAll CMUX_UI_TEST_MODE=1 "$BINARY" > /tmp/cmux-smoke-stdout.log 2>&1 &
+APP_PID=$!
+echo "App PID: $APP_PID"
+
+# --- Verify process is alive after 2s ---
+sleep 2
+if ! kill -0 "$APP_PID" 2>/dev/null; then
+  echo "ERROR: App exited immediately after launch"
+  echo "--- stdout/stderr ---"
+  cat /tmp/cmux-smoke-stdout.log 2>/dev/null | tail -50 || true
+  echo "--- debug log ---"
+  tail -50 /tmp/cmux-debug.log 2>/dev/null || true
+  echo "--- crash reports ---"
+  ls -lt ~/Library/Logs/DiagnosticReports/*cmux* 2>/dev/null | head -5 || echo "(none)"
+  exit 1
+fi
+
+# --- Wait for socket (up to 30s) ---
+echo "Waiting for socket at $SOCKET_PATH..."
+SOCKET_READY=false
+for i in $(seq 1 60); do
+  if [ -S "$SOCKET_PATH" ]; then
+    echo "Socket ready after $((i / 2))s"
+    SOCKET_READY=true
+    break
+  fi
+  # Check if process died while waiting
+  if ! kill -0 "$APP_PID" 2>/dev/null; then
+    echo "ERROR: App crashed while waiting for socket"
+    echo "--- stdout/stderr ---"
+    cat /tmp/cmux-smoke-stdout.log 2>/dev/null | tail -50 || true
+    echo "--- debug log ---"
+    tail -50 /tmp/cmux-debug.log 2>/dev/null || true
+    exit 1
+  fi
+  sleep 0.5
+done
+if [ "$SOCKET_READY" != "true" ]; then
+  echo "ERROR: Socket not ready after 30s"
+  echo "--- stdout/stderr ---"
+  cat /tmp/cmux-smoke-stdout.log 2>/dev/null | tail -30 || true
+  echo "--- debug log ---"
+  tail -30 /tmp/cmux-debug.log 2>/dev/null || true
+  ls -la /tmp/cmux-debug* 2>/dev/null || true
+  pgrep -la "cmux" || echo "No cmux processes found"
+  exit 1
+fi
+
+# --- Ping the socket ---
+echo "Pinging socket..."
+PING_RESPONSE=$(python3 -c "
+import socket
+s = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+s.connect('$SOCKET_PATH')
+s.settimeout(5.0)
+s.sendall(b'ping\n')
+data = s.recv(1024).decode().strip()
+s.close()
+print(data)
+")
+echo "Ping response: $PING_RESPONSE"
+if [ "$PING_RESPONSE" != "PONG" ]; then
+  echo "ERROR: Expected PONG, got: $PING_RESPONSE"
+  exit 1
+fi
+
+# --- Send a command to the terminal ---
+echo "Sending 'time' command to terminal..."
+SEND_RESPONSE=$(python3 -c "
+import socket
+s = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+s.connect('$SOCKET_PATH')
+s.settimeout(5.0)
+s.sendall(b'send time\\\n\n')
+data = s.recv(1024).decode().strip()
+s.close()
+print(data)
+")
+echo "Send response: $SEND_RESPONSE"
+
+# --- Wait and verify stability ---
+echo "Waiting ${STABILITY_WAIT}s to verify stability..."
+sleep "$STABILITY_WAIT"
+
+if ! kill -0 "$APP_PID" 2>/dev/null; then
+  echo "ERROR: App crashed during ${STABILITY_WAIT}s stability check"
+  echo "--- stdout/stderr ---"
+  cat /tmp/cmux-smoke-stdout.log 2>/dev/null | tail -30 || true
+  echo "--- debug log ---"
+  tail -30 /tmp/cmux-debug.log 2>/dev/null || true
+  exit 1
+fi
+
+# --- Final ping ---
+FINAL_PING=$(python3 -c "
+import socket
+s = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+s.connect('$SOCKET_PATH')
+s.settimeout(5.0)
+s.sendall(b'ping\n')
+data = s.recv(1024).decode().strip()
+s.close()
+print(data)
+")
+echo "Final ping: $FINAL_PING"
+if [ "$FINAL_PING" != "PONG" ]; then
+  echo "ERROR: App not responsive after ${STABILITY_WAIT}s"
+  exit 1
+fi
+
+echo "=== Smoke test passed ==="
+
+# --- Cleanup ---
+kill "$APP_PID" 2>/dev/null || true
+wait "$APP_PID" 2>/dev/null || true