v1.6.3 - Content lock fix

Fixed 🔒

Fixed fallback logic in content lock

v1.6.2 had a bug: when the lock was held by another process (not an error), the code still proceeded without the lock via the fallback branch. This could still cause duplicate notifications.

What changed

• Now correctly exits when another process holds the lock
• Only uses fallback on actual errors (e.g., /tmp unavailable)
• Simplified code by removing redundant else branch
• Uses defer for cleaner lock release

How it works now

Process A: acquires lock → checks duplicate → saves state → sends notification → releases lock
Process B: tries to acquire lock → lock busy → exits immediately (no notification)

---

Full Changelog: v1.6.2...v1.6.3