Consistent Enqueue shortcut to match VS Code Copilot's Alt + Enter

### Describe the feature or problem you'd like to solve

Two different shortcuts to remember for VS Code Copilot and Github Copilot

### Proposed solution

- Either make enqueue the default behaviour
- OR, give a quick menu selector to Send immediately, Enqueue or Steer
- OR, allow configurability (I don't want to change my VS Code shortcuts)

### Example prompts or workflows

_No response_

### Additional context

_No response_

Start by reviewing the CLI's current shortcut handling and how VS Code Copilot maps Alt+Enter; the issue names no file or test. Clarify whether the intended outcome is default enqueue, a quick selector, or configurable shortcuts. Done should be a decided shortcut behavior that matches the selected workflow and is covered by appropriate tests.

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