release(v4.12.0): update skill with in-place install and an update admission gate; resume starts the monitor (Issue #72) - archive the review reports, bump the lockstep version

The update skill joins the version matrix and the lockstep test's skill list.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VCgu9Fa9iT7TbJUSzdq4Ff

tests/test_version_consistency.py

@@ -27,6 +27,7 @@ SKILL_NAMES = [
     "multi-agent-mux-delegate-job",
     "multi-agent-mux-loop",
     "multi-agent-mux-orc-onboard",
+    "multi-agent-mux-update",
 ]
 
 
@@ -75,7 +76,7 @@ def _get_skill_md_frontmatter_version(skill_name: str):
 
 
 def test_three_way_version_lockstep():
-    """T-4: lib.sh(MAM_VERSION) == VERSIONS.md(Current + Matrix 8 items) == 8x SKILL.md frontmatters."""
+    """T-4: lib.sh(MAM_VERSION) == VERSIONS.md(Current + Matrix 9 items) == 9x SKILL.md frontmatters."""
     # 1. lib.sh runtime constant
     lib_ver = _get_lib_sh_mam_version()
     assert lib_ver != "", "MAM_VERSION in lib.sh is empty"
@@ -88,7 +89,7 @@ def test_three_way_version_lockstep():
         assert skill in vmd_matrix, f"Skill {skill} missing from VERSIONS.md matrix"
         assert vmd_matrix[skill] == lib_ver, f"VERSIONS.md matrix for {skill} ({vmd_matrix[skill]}) != lib.sh ({lib_ver})"
 
-    # 3. 8x SKILL.md files
+    # 3. 9x SKILL.md files
     for skill in SKILL_NAMES:
         fm_ver = _get_skill_md_frontmatter_version(skill)
         assert fm_ver == lib_ver, f"{skill}/SKILL.md version ({fm_ver}) != lib.sh ({lib_ver})"