fix(tui): preserve generated session titles

[opencode-agent]

Summary

• apply live session rename events after any in-flight session hydration
• prevent a stale initial response from replacing a generated session title
• cover the title-generation/hydration race through the TUI lifecycle

This is a race-condition follow-up to #35464 and #35610. The prior fix made terminal titles observe the V2 store, but a generated session.renamed event could still arrive before that store contained the new session and be lost.

Testing

• bun test --timeout 30000 --only-failures in packages/tui (521 pass, 5 skip)
• bun typecheck in packages/tui
• lifecycle regression test repeated 5 times

Requested by: @rekram1-node (Aiden Cline via Slack)

[kitlangton]

Superseded by #39894, which preserves generated titles across initial hydration and also fixes the shared tab persistence feedback loop. #39894 is merged, so closing this one. Thanks for identifying the original hydration race.