feat(review): Add expanded review comment editor

[leoreisdias]

Context

Long agent-generated review comments can be awkward to read or edit in the compact inline review annotation toolbar. The compact composer is still useful for quick comments, but larger findings need a first-class expanded writing space.

What Changed

• Added an expand control to the code-review annotation toolbar.
• Added a review-specific expanded comment dialog that edits the same existing toolbar comment state.
• Preserved the compact toolbar as the default surface, including the original w-80 starting width.
• Kept textarea vertical resize in the compact composer for a lightweight inline improvement.
• Left suggested-code expansion on the existing suggestion modal path.

GIF

Review Focus

• Confirm the expanded dialog uses the existing review annotation state correctly for both add and edit flows.
• Check the collapse vs close behavior: collapse returns to the compact toolbar, close cancels the annotation like the existing compact close button.
• Verify the modal does not interfere with the existing suggested-code modal or outside-dismiss behavior.

Test Plan

• env PATH=/Users/leonardo/.codex/worktrees/91ae/plannotator/node_modules/.bun/typescript@5.8.3/node_modules/.bin:$PATH bun run typecheck
• bun run build:review
• bun run build:hook
• Opened a local plannotator review session and exercised the new expanded comment editor path.