feat(app): UX - session dock keyboard nav

[neriousy]

Issue for this PR

Closes #16752

Type of change

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

What does this PR do?

Adds keyboard navigation to question dock

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How did you verify your code works?

1. Ask agent to ask you a question using question tool
2. Use keyboard navigation

Screenshots / recordings

2026-03-09.16-22-39.mp4

Checklist

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

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[Copilot]

Pull request overview

This PR adds full keyboard navigation support to the question dock component in the desktop app. Users can now navigate options, select answers, and move between questions entirely using the keyboard, addressing issue #16752.

Changes:

• Adds keyboard event handling (handleKeyDown) to the question dock supporting arrow keys (up/down for options, left/right for questions), Enter/Space for selection, and Home/End for jumping to first/last option
• Adds keyboard shortcut hints UI in the dock footer, with translations across all 17 locale files
• Adds focus management (focusOption, focusFirstOption) with retry logic, focus-visible CSS styles, and createEffect to auto-focus the first option on tab change

Reviewed changes

Copilot reviewed 20 out of 20 changed files in this pull request and generated 1 comment.

File	Description
packages/app/src/pages/session/composer/session-question-dock.tsx	Core keyboard navigation logic: keydown handler, focus management, auto-focus effect, keyboard hint data, and type="button" additions
packages/ui/src/components/message-part.css	Focus-visible styles for question options, keyboard hints styling, and footer layout adjustments (gap, flex-wrap)
packages/app/e2e/session/question-dock-keyboard.spec.ts	New e2e test suite covering arrow navigation, Enter/Space selection, Home/End, multi-select toggling, and cross-question navigation
packages/ui/src/i18n/*.ts (17 files)	New translation keys for keyboard hint labels (move, select, prev, next, submit, save, newline, cancel, submit all, jump to question)

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[adamdotdevin]

@neriousy Let's not put any keyboard hints at the bottom and also the selected state should look like other list selection states throughout the app (no blue outline)

[neriousy]

@adamdotdevin removed the outline & removed the hints. Updated also the showcase video

I also noticed that on hard page refresh the answers are not persisted. Should I add it in a different pr?