Auto-focus message composer on keypress with user toggle

[AlexProgrammerDE]

First time contributor checklist:

• I have read the README and Contributor Guidelines
• I have signed the Contributor Licence Agreement

Contributor checklist:

• My contribution is not related to translations.
• My commits are in nice logical chunks with good commit messages
• My changes are rebased on the latest main branch
• A pnpm run ready run passes successfully (more about tests here)
• My changes are ready to be shipped to users

Summary

• Auto-focuses the message composition input when a printable key is pressed anywhere
  in the conversation view, matching behavior of Telegram, WhatsApp, Discord, and Slack
• Adds a user-facing toggle in Settings > Chats (default: on) to disable for
  privacy-conscious users
• Supersedes Focus on composition area when pressing a key #4998 with a clean implementation addressing all review feedback

Changes

• New setting typingAutoFocus (Storage, Redux selector, Preferences UI)
• useDocumentKeyDown hook in CompositionArea with guards for:
  • Modifier keys (Ctrl/Cmd/Alt) to avoid shortcut interference
  • Active input/textarea/select/contenteditable elements
  • Non-printable keys (arrows, F-keys, Escape, etc.)
  • Feature toggle check

Edge cases handled

• Other input fields focused (search, settings) — no focus steal
• Keyboard shortcuts (Ctrl+C, Cmd+V) — ignored
• Panels/overlays open — composer not rendered, so no conflict
• App not visible — Electron won't deliver keydown events to unfocused windows

Test plan

• Type with composer unfocused — auto-focuses and captures keystroke
• Type in search bar — stays in search
• Use keyboard shortcuts — no interference
• Disable in Settings > Chats — typing no longer auto-focuses
• Setting persists across app restart
• Storybook stories render correctly

[Copilot]

Pull request overview

This PR implements an auto-focus feature for the message composition area that focuses the input when a printable key is pressed anywhere in the conversation view. It includes a user-facing toggle in Settings > Chats (defaulting to on) and supersedes PR #4998.

Changes:

• Adds typingAutoFocus setting with storage, Redux selector, and UI toggle
• Implements keyboard event listener in CompositionArea using useDocumentKeyDown hook with guards for modifier keys, active inputs, and non-printable keys
• Updates localization strings with title and description for the new setting

Reviewed changes

Copilot reviewed 9 out of 10 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
ts/types/StorageUIKeys.std.ts	Adds 'typingAutoFocus' to the UI storage keys array
ts/types/Storage.d.ts	Defines typingAutoFocus as a boolean in StorageAccessType
ts/state/smart/Preferences.preload.tsx	Creates storage accessor and passes toggle state/handler to Preferences component
ts/state/smart/CompositionArea.preload.tsx	Adds selector and passes isTypingAutoFocusEnabled to CompositionArea
ts/state/selectors/items.dom.ts	Creates getTypingAutoFocus selector with default value of true
ts/components/Preferences.dom.tsx	Adds checkbox UI for the typing auto-focus setting in Chats section
ts/components/Preferences.dom.stories.tsx	Updates story with hasTypingAutoFocus and handler for testing
ts/components/CompositionArea.dom.tsx	Implements keyboard listener with guards and calls focus() on printable key press
ts/components/CompositionArea.dom.stories.tsx	Adds isTypingAutoFocusEnabled prop to story
_locales/en/messages.json	Adds English strings for title and description of the new setting

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[AlexProgrammerDE]

CLA is signed. This is one of they key reasons I currently do not want to switch from e.g. WhatsApp and Discord to Signal. Having to manually focus the small message input box perfectly every time I wanna send a message (while it isnt focused but I am on the right page with the right intention) is tedious and other social media desktop apps have it figured out and it works wonderfully. This PR would finally bring this quality of life feature to Signal!

[ethanp4]

I'd be happy to see this merged

[karlhorky]

@scottnonnenberg-signal @josh-signal what do you think about this PR? Does this address your concerns from the other PR #4998?

cc @indutny-signal, since you are assigned to PR #4998