Clarify scrub audit return contract

Remove the obsolete CLEAN branch beneath the audit prompt's Otherwise return instruction. CLEAN remains governed by the preceding no-misses condition, and MISSED is now the only alternative. Verified with the focused structural test and git diff --check.

skills/diagnosing-superpowers/prompts/scrub-audit.md

@@ -22,12 +22,6 @@ available for the findings.
 Return CLEAN only if no policy misses or unresolved classifications remain.
 Otherwise return:
 
-```
-CLEAN
-```
-
-or
-
 ```
 MISSED
 - <file>:<line> — <category> — <non-sensitive description or classification question>