chore(Item 11 tail): resolve 10 stale .md (keep canonical .adoc) + 2 .md→.adoc conversions

Day 10 lossy-tail, Day-9-style hybrid resolution:
- DELETE_MD: .md was broken/auto-gen scaffold cruft; coherent .adoc retained.
- CONVERT: .md was the real doc; faithfully converted to AsciiDoc via pandoc
  3.9 (union-merge: any legacy .adoc-only content preserved verbatim).
Inbound links repointed .md→.adoc. No content lost. FLAG-class ambiguous
pairs intentionally deferred.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: hyperpolymath