ui(redis): mounted guard after await in key editor saves

[ZhuchkaTriplesix]

Parent

Part of #445

Severity

Low

Problem

Post-await setState without mounted check on save paths → dispose race can crash. Load path already guards.

Evidence

• lib/features/redis/redis_key_editor.dart (~117–131 and similar saves)

Acceptance

• All post-await setState paths check mounted
• Closing editor mid-save does not throw

Suggested fix

if (!mounted) return before each setState after await (parity with load).

[ZhuchkaTriplesix]

Shipped on dev via #462 (Closes did not auto-close because PRs targeted dev).