Add two new throttle utility methods: createAsyncThrottle and createExecutionLock for safe async operation locking. Update the existing throttle method's comment to clarify traditional timestamp usage. Replace DebounceUtils usage with ThrottleUtils.createExecutionLock in order footer and booking page payment handlers to prevent duplicate payments. Rewrite uni.requestPayment calls to use Promise wrapping for proper async handling, and add try/catch/finally blocks to ensure loading state is always cleaned up correctly. Fix template formatting and trailing commas across modified files.
