Report a rune's actual universal attributes in refrakt reference

Acceptance Criteria

• The blanket "available on every rune" claim is gone
• The universal attributes reported for a rune are the ones its schema actually carries, read from the schema rather than from a static list
• --format json reports the same narrowed set, so machine consumers agree with the human output
• refrakt reference list and refrakt reference dump are consistent with the single-rune output
• No theme config is loaded to produce it
• A test pins the correction against a rune with known-inapplicable attributes, so the false claim cannot return
• AGENTS.md (or whatever dump --check guards) is regenerated if its content shifts
• npm run build and the full repo suite pass