feat(amazonq): add keyboard shortcut for stop/reject/run commands

[dungdong-aws]

Problem

Currently, users need to manually click buttons or use the command palette to execute common shell
commands (reject/run/stop) in the IDE. This creates friction in the developer workflow, especially
for power users who prefer keyboard shortcuts.

Solution

Reopen Na's PR that added keyboard shortcuts for reject/run/stop shell commands

Update to align with new requirements.

Add VS Code feature flag (shortcut)

Only available if Q is focused

Screenshots

Screen.Recording.2025-07-18.at.12.27.40.AM.mov

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[github-actions]

• This pull request modifies code in src/* but no tests were added/updated.
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