fix(merge-queue): add remove_label function needed by ApiError handler

The ApiError handler (added in 7c08352d) calls remove_label() to strip
the queue label from PRs blocked by pre-receive hooks, but the function
was never defined — causing NameError on the first merge failure and
crashing the workflow tick.

Fixes: mc#1144 (queue stalls after pre-receive hook 405)
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

.gitea/scripts/gitea-merge-queue.py

@@ -314,6 +314,29 @@ def post_comment(pr_number: int, body: str, *, dry_run: bool) -> None:
     api("POST", f"/repos/{OWNER}/{NAME}/issues/{pr_number}/comments", body={"body": body})
 
 
+def remove_label(pr_number: int, label: str, *, dry_run: bool) -> None:
+    print(f"::notice::removing label '{label}' from PR #{pr_number}")
+    if dry_run:
+        return
+    # Gitea requires label ID, not name, for deletion.
+    # Multiple labels can share the same name with different IDs — remove all.
+    _, body = api("GET", f"/repos/{OWNER}/{NAME}/pulls/{pr_number}")
+    pr_labels = body.get("labels", []) if isinstance(body, dict) else []
+    removed = False
+    for lbl in pr_labels:
+        if lbl.get("name") == label:
+            label_id = lbl.get("id")
+            if label_id:
+                api(
+                    "DELETE",
+                    f"/repos/{OWNER}/{NAME}/issues/{pr_number}/labels/{label_id}",
+                    expect_json=False,
+                )
+                removed = True
+    if not removed:
+        print(f"::notice::label '{label}' not found on PR #{pr_number}")
+
+
 def update_pull(pr_number: int, *, dry_run: bool) -> None:
     print(f"::notice::updating PR #{pr_number} with base branch via style={UPDATE_STYLE}")
     if dry_run:

workspace-server/internal/handlers/external_connection.go

@@ -646,8 +646,12 @@ const externalOpenClawTemplate = `# OpenClaw MCP config — outbound tool path.
 # external machine today, pair with the Python SDK tab.
 
 # 1. Install openclaw CLI + the workspace runtime wheel:
+#    The version pin (>=0.1.999) ensures the "molecule-mcp" console
+#    script is present — it is what keeps the workspace ALIVE on canvas
+#    (register-on-startup + 20s heartbeat). Older versions only ship
+#    a2a_mcp_server which does not heartbeat.
 npm install -g openclaw@latest
-pip install molecule-ai-workspace-runtime
+pip install "molecule-ai-workspace-runtime>=0.1.999"
 
 # 2. Onboard openclaw against your model provider (one-time setup).
 #    --non-interactive needs an explicit --provider + --model so it