[Feature]: Expose "Implement in new thread" as a keybindable command

[m4littlemozarts]

Before submitting

• I searched existing issues and did not find a duplicate.
• I am describing a concrete problem or use case, not just a vague idea.

Area

apps/desktop

Problem or use case

After finishing a plan in Plan Mode, the "Implement in new thread" option (accessible via the dropdown arrow on the blue Implement button) is a great workflow — it clears context and starts fresh with just the plan. However, this action is only accessible through the GUI dropdown and has no corresponding command ID in the keybindings system.

The current bindable commands in ~/.t3/keybindings.json are limited to terminal.*, diff.toggle, chat.new, chat.newLocal, editor.openFavorite, and script.{id}.run. There's no way to trigger "Implement in new thread" from a keyboard shortcut.

Proposed solution

Expose "Implement in new thread" as a bindable command (e.g. plan.implementNewThread) so users can add it to ~/.t3/keybindings.json with a when clause for plan mode context. Something like:

{
  "key": "mod+shift+i",
  "command": "plan.implementNewThread",
  "when": "planReady"
}

Why this matters

Plan Mode → clear context → implement is one of the most powerful workflows in T3 Code. Being able to trigger it with a single keystroke instead of navigating a dropdown menu would make the experience much smoother, especially for users who rely heavily on Plan Mode for complex tasks.

Smallest useful scope

Add a command ID for the existing "Implement in new thread" action so it can be bound in keybindings.json.

Alternatives considered

Using chat.new (Cmd+Shift+N) to manually open a fresh thread, but this doesn't carry the plan artifact forward automatically like the dedicated button does.

Contribution

• I would be open to helping implement this.