RESULT: FAILED

FILES CHANGED:
- commonmark
- renderer/html.py

SUMMARY:
Added the expected executable and implemented balanced link/image parsing. Focused tests still fail on nested-link and edge-case precedence behavior.

BLOCKERS:
- Inline-links scope is not passing.
- Full suite remains failing on existing block-parser cases.

FAILURE_SUMMARY: Link parser regression remains.

FAILURE_DETAIL: Legacy inline substitutions still conflict with the new scanner, producing incorrect nested-link and reference-link output. Reconcile or replace the fallback substitutions before rerunning.