[Feature Request] Add SessionRenamed hook event for external system integration

Bug Description
Feature request: Add a "SessionRenamed" hook event that fires when a session is renamed. Use case: automatically syncing the session name to external systems like tmux window titles. Currently there's no hook event for this and no workaround.

Environment Info

• Platform: darwin
• Terminal: tmux
• Version: 2.1.104
• Feedback ID: fc63ee20-fc35-4c01-a556-a808a581d9e8

Errors

[{"error":"Error: NON-FATAL: Lock acquisition failed for /Users/marwantanager/.local/share/claude/versions/2.1.104 (expected in multi-process scenarios)\n    at Tc_ (/$bunfs/root/src/entrypoints/cli.js:2836:2153)\n    at Se6 (/$bunfs/root/src/entrypoints/cli.js:2836:1233)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-04-21T23:47:30.889Z"}]