feat(infra): schedule daily model profile refresh with job summary (#35354)

- Schedules the `refresh_model_profiles` workflow to run daily at 08:00
UTC (manual trigger available).
- Adds a job summary step that reports whether a PR was created/updated
or skipped because profiles were already up to date.
- Each run supersedes any stale PR from a previous run since the action
force-pushes to a fixed branch (`bot/refresh-model-profiles`).