refactor(i18n): use grammar engine for progress messages
- Replace cli.progress.* keys with i18n.P() dynamic generation
- Remove 7 static progress keys from en_GB.json (building, checking, etc.)
- Add additional core.* intents (format, analyse, link, unlink, fetch, etc.)
- Add grammar helpers: Progress(), ProgressSubject(), ActionResult(), Label()
- Add package-level convenience functions: P(), PS(), L()
- Update commands to use common.prompt.abort instead of cli.confirm.abort
The grammar engine now generates progress messages dynamically:
i18n.P("check") → "Checking..."
i18n.P("fetch") → "Fetching..."
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>