Add route diagram page with execution overlay and group-aware APIs

Backend: Add group filtering to agent list, search, stats, and timeseries
endpoints. Add diagram lookup by group+routeId. Resolve application group
to agent IDs server-side for ClickHouse IN-clause queries.

Frontend: New route detail page at /apps/{group}/routes/{routeId} with
three tabs (Diagram, Performance, Processor Tree). SVG diagram rendering
with panzoom, execution overlay (glow effects, duration/sequence badges,
flow particles, minimap), and processor detail panel. uPlot charts for
performance tab replacing old SVG sparklines. Ctrl+Click from
ExecutionExplorer navigates to route diagram with overlay.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ui/src/api/openapi.json

@@ -236,6 +236,14 @@
               "type": "string"
             }
           },
+          {
+            "name": "group",
+            "in": "query",
+            "required": false,
+            "schema": {
+              "type": "string"
+            }
+          },
           {
             "name": "offset",
             "in": "query",
@@ -933,6 +941,22 @@
               "type": "string",
               "format": "date-time"
             }
+          },
+          {
+            "name": "routeId",
+            "in": "query",
+            "required": false,
+            "schema": {
+              "type": "string"
+            }
+          },
+          {
+            "name": "group",
+            "in": "query",
+            "required": false,
+            "schema": {
+              "type": "string"
+            }
           }
         ],
         "responses": {
@@ -984,6 +1008,22 @@
               "format": "int32",
               "default": 24
             }
+          },
+          {
+            "name": "routeId",
+            "in": "query",
+            "required": false,
+            "schema": {
+              "type": "string"
+            }
+          },
+          {
+            "name": "group",
+            "in": "query",
+            "required": false,
+            "schema": {
+              "type": "string"
+            }
           }
         ],
         "responses": {
@@ -1097,6 +1137,49 @@
         }
       }
     },
+    "/diagrams": {
+      "get": {
+        "tags": [
+          "Diagrams"
+        ],
+        "summary": "Find diagram by application group and route ID",
+        "description": "Resolves group to agent IDs and finds the latest diagram for the route",
+        "operationId": "findByGroupAndRoute",
+        "parameters": [
+          {
+            "name": "group",
+            "in": "query",
+            "required": true,
+            "schema": {
+              "type": "string"
+            }
+          },
+          {
+            "name": "routeId",
+            "in": "query",
+            "required": true,
+            "schema": {
+              "type": "string"
+            }
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Diagram layout returned",
+            "content": {
+              "*/*": {
+                "schema": {
+                  "$ref": "#/components/schemas/DiagramLayout"
+                }
+              }
+            }
+          },
+          "404": {
+            "description": "No diagram found for the given group and route"
+          }
+        }
+      }
+    },
     "/diagrams/{contentHash}/render": {
       "get": {
         "tags": [
@@ -1191,7 +1274,7 @@
           "Agent Management"
         ],
         "summary": "List all agents",
-        "description": "Returns all registered agents, optionally filtered by status",
+        "description": "Returns all registered agents, optionally filtered by status and/or group",
         "operationId": "listAgents",
         "parameters": [
           {
@@ -1201,6 +1284,14 @@
             "schema": {
               "type": "string"
             }
+          },
+          {
+            "name": "group",
+            "in": "query",
+            "required": false,
+            "schema": {
+              "type": "string"
+            }
           }
         ],
         "responses": {
@@ -1509,6 +1600,15 @@
           "processorType": {
             "type": "string"
           },
+          "group": {
+            "type": "string"
+          },
+          "agentIds": {
+            "type": "array",
+            "items": {
+              "type": "string"
+            }
+          },
           "offset": {
             "type": "integer",
             "format": "int32"
@@ -2119,6 +2219,12 @@
           "height": {
             "type": "number",
             "format": "double"
+          },
+          "children": {
+            "type": "array",
+            "items": {
+              "$ref": "#/components/schemas/PositionedNode"
+            }
           }
         }
       },