Ignore shell path terminal titles

[ymichael]

Summary

• Ignore automatic shell path titles like user@host:/worktree and user@host: /worktree
• Keep the daemon's initial shell-name terminal title instead of replacing it with a long worktree path
• Add regression coverage for Linux bash-style title spacing

Tests

• pnpm exec turbo run test --filter=@bb/app -- src/components/thread/terminal/thread-terminal-title.test.ts
• pnpm exec turbo run typecheck --filter=@bb/app