fix(telemetry): recover worker agent and Tailscale transport automatically

tests/test_compute_contour_api.py

@@ -144,3 +144,17 @@ def test_contour_router_returns_404_for_unknown_contour(tmp_path: Path) -> None:
     with pytest.raises(HTTPException) as error:
         install("missing")
     assert error.value.status_code == 404
+
+
+def test_broker_apply_uses_explicit_installation_root(tmp_path, monkeypatch):
+    from k1link.web import compute_contour_api as api
+    root = tmp_path / 'prepared-stack'
+    monkeypatch.setenv('MISSIONCORE_TELEMETRY_PLANE_ROOT', str(root))
+    seen = []
+    def apply(target, installation):
+        seen.append(installation)
+        return {'ready': True}
+    monkeypatch.setattr(api, 'apply_broker_network', apply)
+    router = api.build_compute_contour_router(root_provider=lambda: tmp_path / 'system')
+    _endpoint(router, '/api/v1/system/contours/{contour_id}/network/broker', 'POST')('worker-006')
+    assert seen == [root]