feat(tui): add default vscode themes collection

[n24q02m]

Issue for this PR

Closes #4887

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

Expands the built-in TUI themes to include familiar VSCode-based themes: VSCode Dark, VSCode Light, and Tomorrow Night Blue. These have been added to the defs and the dialog list, allowing users to easily select them from the TUI theme menu.

How did you verify your code works?

Launched the TUI, opened the theme dialog, selected each new theme, and verified that colors apply correctly. Passed bun run typecheck and bun run test.

Screenshots / recordings

N/A

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR

[github-actions]

Thanks for your contribution!

This PR doesn't have a linked issue. All PRs must reference an existing issue.

Please:

1. Open an issue describing the bug/feature (if one doesn't exist)
2. Add Fixes #<number> or Closes #<number> to this PR description

See CONTRIBUTING.md for details.

[github-actions]

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

Based on the search results, I found one potentially related PR:

Related PR:

• PR feat(tui): base16 theme #4887: "feat(tui): base16 theme" - feat(tui): base16 theme #4887

This PR may be related as it also deals with adding themes to the TUI. You may want to check if #4887 already implements VSCode theme support or if there's overlap in the theme management approach.

[github-actions]

Thanks for updating your PR! It now meets our contributing guidelines. 👍

[n24q02m]

I'll be publishing these themes as a standalone NPM plugin instead to keep the core binary small and allow for independent updates. Thank you!