Teach the scanner its own README catch

[calebstacy]

What changed

• replaces “That distinction is the point” with the policy decision itself
• teaches anaphoric-evaluation to catch that self-announcing surface form
• adds both a positive specimen and a legitimate neighbor
• applies the remaining medium self-lint repair in the move catalog
• bumps the release to 0.2.1

Verification

• 137 tests pass
• README, skill, move catalog, and both examples all scan CLEAN
• skill validator passes
• fresh sdist and wheel build