fix(monitoring): pre-format display string in Flask instead of Infinity

Infinity datasource doesn't support concat() function in JSONata.
Move string formatting to Flask backend and return pre-formatted
'display' field. Remove computed_columns from dashboard panel.

Author: claude

config/grafana/dashboards/Self_Monitoring_Dashboard.json

@@ -100,12 +100,7 @@
           "url_options": {
             "method": "GET"
           },
-          "computed_columns": [
-            {
-              "selector": "concat('PostgresAI v', version, ' (built: ', build_ts, ')')",
-              "text": "display"
-            }
-          ]
+          "computed_columns": []
         }
       ],
       "title": "",

monitoring_flask_backend/app.py

@@ -54,9 +54,11 @@ def read_version_file(filepath, default='unknown'):
 @app.route('/version', methods=['GET'])
 def version():
     """Return application version and build timestamp as array for Grafana Infinity datasource"""
+    display = f"PostgresAI v{APP_VERSION} (built: {APP_BUILD_TS})"
     return jsonify([{
         "version": APP_VERSION,
-        "build_ts": APP_BUILD_TS
+        "build_ts": APP_BUILD_TS,
+        "display": display
     }])
 
 

monitoring_flask_backend/test_app.py

@@ -42,6 +42,13 @@ def test_version_endpoint_contains_build_ts_field(self, client):
         data = json.loads(response.data)
         assert 'build_ts' in data[0]
 
+    def test_version_endpoint_contains_display_field(self, client):
+        """Test that /version response contains pre-formatted display field."""
+        response = client.get('/version')
+        data = json.loads(response.data)
+        assert 'display' in data[0]
+        assert 'PostgresAI v' in data[0]['display']
+
 
 class TestReadVersionFile:
     """Tests for the read_version_file function."""