feat: mount canonical gitea-workflow skill for Codex and MCP inventory (Closes #551)

Expose gitea-workflow / llm-project-workflow / git-pr-workflows as one
workflow router in mcp_list_project_skills, add preflight + Codex install
script, and document multi-runtime skill name parity.

gitea_mcp_server.py

@@ -827,6 +827,7 @@ import reconciliation_workflow  # noqa: E402
 import audit_reconciliation_mode  # noqa: E402
 import review_merge_state_machine  # noqa: E402
 import pr_work_lease  # noqa: E402
+import workflow_skill  # noqa: E402
 import native_mcp_preference  # noqa: E402
 import worktree_cleanup_audit  # noqa: E402
 
@@ -6933,6 +6934,9 @@ _PROJECT_SKILLS = {
     },
 }
 
+# Canonical workflow router skill names for Claude/Codex/Gemini parity (#551).
+_PROJECT_SKILLS.update(workflow_skill.workflow_skill_registry_entries())
+
 
 @mcp.tool()
 def mcp_get_control_plane_guide(
@@ -7046,7 +7050,7 @@ def mcp_get_control_plane_guide(
 
 @mcp.tool()
 def mcp_list_project_skills() -> dict:
-    """List the project's workflow skills and when to use them (#128).
+    """List the project's workflow skills and when to use them (#128, #551).
 
     Read-only; makes no API calls. Each skill reports its name,
     description, when-to-use guidance, required operations, status
@@ -7054,6 +7058,9 @@ def mcp_list_project_skills() -> dict:
     'operator-only'), and whether the current profile's operations permit it. Use
     mcp_get_skill_guide(name) for the step-by-step guide.
 
+    Includes the canonical workflow router under gitea-workflow,
+    llm-project-workflow, and git-pr-workflows (#551).
+
     Returns:
         dict with 'read_only', 'count', and 'skills' (list). Never secrets.
     """
@@ -7078,10 +7085,39 @@ def mcp_list_project_skills() -> dict:
         }
         if meta.get("notes"):
             entry["notes"] = meta["notes"]
+        if meta.get("repo_path"):
+            entry["repo_path"] = meta["repo_path"]
+        if meta.get("canonical"):
+            entry["canonical"] = True
         skills.append(entry)
     return {"read_only": True, "count": len(skills), "skills": skills}
 
 
+@mcp.tool()
+def mcp_check_workflow_skill_preflight(
+    project_root: str | None = None,
+) -> dict:
+    """Fail-closed preflight for the canonical workflow skill wall (#551).
+
+    Verifies skills/llm-project-workflow/SKILL.md exists in the project tree
+    and reports whether Codex has a matching mount under ~/.codex/skills.
+    Call before git/Gitea mutations when the controller requires gitea-workflow.
+
+    Args:
+        project_root: Optional override; defaults to this MCP process root.
+
+    Returns:
+        dict with workflow_skill_ready, blocked, canonical_names, codex mount
+        status, and safe_next_action. Never secrets.
+    """
+    root = (project_root or PROJECT_ROOT).strip()
+    result = workflow_skill.assess_workflow_skill_presence(root)
+    result["success"] = not result.get("blocked")
+    result["project_root"] = root
+    result["read_only"] = True
+    return result
+
+
 @mcp.tool()
 def mcp_get_skill_guide(skill_name: str) -> dict:
     """Step-by-step guide for one named project skill (#128).