Lock MASTER_ROADMAP_ENGINE.md post-finalization.

Prevents any non-status changes going forward.

PR: LEVEL 24.3 ROADMAP LOCK

Author: DavidQ

docs/dev/reports/roadmap_lock_report.txt

@@ -0,0 +1,10 @@
+Roadmap Lock Report
+
+MASTER_ROADMAP_ENGINE.md is now locked.
+
+Rules:
+- No text modification
+- No deletion
+- Status updates only when validation-backed
+
+Status: LOCKED

docs/dev/validation_checklist.txt

@@ -1,8 +1,5 @@
 Validation Checklist
 
-[x] Guard rules persist
-[x] Monitoring defined
-[x] No regression introduced
-[x] Fullscreen scan command documented for reuse
-[x] `FullscreenRuleEnforcement` test reuse documented
-[x] `FullscreenAbility0713ViewportFit` test reuse documented
+[ ] Roadmap locked
+[ ] Guard rules documented
+[ ] No further structural edits allowed

docs/pr/BUILD_PR_LEVEL_24_3_ROADMAP_POST_FINAL_AUDIT_LOCK.md

@@ -0,0 +1,14 @@
+# BUILD PR LEVEL 24.3
+## Roadmap Post-Final Audit Lock
+
+### Purpose
+Lock MASTER_ROADMAP_ENGINE.md after finalization and prevent any non-compliant edits.
+
+### Scope
+- Enforce status-only modification rule permanently
+- Prevent roadmap rewrite or deletion
+- Require validation-backed updates only
+
+### Acceptance
+- Roadmap treated as locked artifact
+- Any future change must follow status-only rule