Adds a new `/core:release` command to streamline the release process for modules.
This command automates the following workflow:
- Bumps the version in `package.json` (and `gemini-extension.json` if it exists).
- Generates a `CHANGELOG.md` entry from conventional commit messages.
- Commits the changes with a `chore(release): vX.Y.Z` message.
- Creates and pushes a new git tag to trigger the CI release.
A `--preview` flag is included to allow for a dry run of the release process without making any changes.
This commit introduces a new /core:clean command to clean up generated files, caches, and build artifacts.
The command provides the following options:
- /core:clean: Cleans all caches and build artifacts.
- /core:clean --cache: Cleans caches only.
- /core:clean --deps: Performs a dry-run for dependency cleanup.
- /core:clean --deps --force: Deletes dependency directories after a confirmation prompt.
- /core:clean --dry-run: Shows what would be deleted without performing any actions.
The implementation includes safety features such as a "dry-run by default" for dependency cleaning and a confirmation prompt for destructive operations.
