Fix scope ambiguity in ponytail-audit and ponytail-review Boundaries (#163)

The Boundaries line opened with "Complexity only, correctness bugs, security
holes, and performance go to a normal review pass." The comma after "Complexity
only" fuses the in-scope item with the out-of-scope list, so a model parsing it
literally can read all four categories as targets of the audit — the opposite of
intent.

Restate the boundary as an explicit scope fence: name what is in scope, then
mark correctness/security/performance as explicitly out of scope. "Out of scope"
is phrasing models reliably honor as a constraint. Also aligns the scope term
with each skill's stated purpose (over-engineering).

Applied to both skills/ and the .openclaw/ mirror so the two trees stay in sync.

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>