fix(tui): submit prompt when resuming session

[pacaplan]

Fixes #37536

Summary

• carry the startup prompt into session routes selected by --session, --continue, or their fork variants
• wait for the prompt ref, model state, and resumed-session synchronization before submitting
• share an exactly-once startup prompt controller between fresh and resumed TUI routes
• preserve user edits instead of auto-submitting changed prompt text

Testing

• bun test test/cli/tui/startup-prompt.test.ts
• bun run typecheck in packages/tui
• bun test --timeout 30000 --only-failures in packages/tui (193 passed, 1 skipped)
• bun run lint

[github-actions]

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[github-actions]

The following comment was made by an LLM, it may be inaccurate:

Potential Duplicate Found:

• PR feat(tui): implement prompt submit when used with a specific session command (--session, --continue, --fork) in the CLI #14442: feat(tui): implement prompt submit when used with a specific session command (--session, --continue, --fork) in the CLI
  • feat(tui): implement prompt submit when used with a specific session command (--session, --continue, --fork) in the CLI #14442
  • This PR appears to address the same feature: submitting prompts when using --session, --continue, or fork variants in the CLI.

This looks like it could be related functionality or a historical attempt at solving the same problem. You may want to check if #14442 was closed/not merged and whether this PR (#37539) is a fresh attempt or improvement on that work.

[github-actions]

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