refactor(LGraph): dispatch trigger events through events target

Adds the four node trigger event payloads (property/slot-errors/
slot-links/slot-label) to LGraphEventMap and makes LGraph.trigger()
dispatch via this.events in addition to calling onTrigger.

Removes the leaky onTrigger monkey-patch in AppModeWidgetList.vue,
replacing it with useEventListener on the events target. The
onTrigger callback path is preserved for back-compat with
useGraphNodeManager (see FE-667 for converting that one too).

src/components/builder/AppModeWidgetList.vue

@@ -1,6 +1,6 @@
 <script setup lang="ts">
 import { useEventListener } from '@vueuse/core'
-import { computed, onBeforeUnmount, provide, shallowRef, triggerRef } from 'vue'
+import { computed, provide, shallowRef, triggerRef } from 'vue'
 
 import { useAppModeWidgetResizing } from '@/components/builder/useAppModeWidgetResizing'
 import { useI18n } from 'vue-i18n'
@@ -63,17 +63,9 @@ useEventListener(
   'configured',
   () => (graphNodes.value = app.rootGraph.nodes)
 )
-// `LGraph.trigger()` invokes `onTrigger` synchronously but does not dispatch
-// on `events`, so chain through `onTrigger` to react to slot-label renames.
-const previousOnTrigger = app.rootGraph.onTrigger
-app.rootGraph.onTrigger = (event) => {
-  previousOnTrigger?.(event)
-  if (event.type === 'node:slot-label:changed') triggerRef(graphNodes)
-}
-onBeforeUnmount(() => {
-  if (app.rootGraph.onTrigger === undefined) return
-  app.rootGraph.onTrigger = previousOnTrigger
-})
+useEventListener(app.rootGraph.events, 'node:slot-label:changed', () =>
+  triggerRef(graphNodes)
+)
 
 const mappedSelections = computed((): WidgetEntry[] => {
   void graphNodes.value

src/lib/litegraph/src/LGraph.ts

@@ -1364,18 +1364,17 @@ export class LGraph
   ): void
   trigger(action: string, param: unknown): void
   trigger(action: string, param: unknown) {
-    // Convert to discriminated union format for typed handlers
-    const validEventTypes = new Set([
+    const validEventTypes = new Set<LGraphTriggerAction>([
       'node:slot-links:changed',
       'node:slot-errors:changed',
       'node:property:changed',
       'node:slot-label:changed'
     ])
+    if (!validEventTypes.has(action as LGraphTriggerAction)) return
+    if (!param || typeof param !== 'object') return
 
-    if (validEventTypes.has(action) && param && typeof param === 'object') {
-      this.onTrigger?.({ type: action, ...param } as LGraphTriggerEvent)
-    }
-    // Don't handle unknown events - just ignore them
+    this.onTrigger?.({ type: action, ...param } as LGraphTriggerEvent)
+    this.events.dispatch(action as LGraphTriggerAction, param as never)
   }
 
   /** @todo Clean up - never implemented. */

src/lib/litegraph/src/infrastructure/LGraphEventMap.ts

@@ -1,7 +1,9 @@
 import type { LGraph } from '@/lib/litegraph/src/LGraph'
+import type { NodeId } from '@/lib/litegraph/src/LGraphNode'
 import type { LLink, ResolvedConnection } from '@/lib/litegraph/src/LLink'
 import type { ReadOnlyRect } from '@/lib/litegraph/src/interfaces'
 import type { Subgraph } from '@/lib/litegraph/src/subgraph/Subgraph'
+import type { NodeSlotType } from '@/lib/litegraph/src/types/globalEnums'
 import type {
   ExportedSubgraph,
   ISerialisedGraph,
@@ -48,4 +50,23 @@ export interface LGraphEventMap {
     subgraph: Subgraph
     closingGraph: LGraph | Subgraph
   }
+
+  'node:property:changed': {
+    nodeId: NodeId
+    property: string
+    oldValue: unknown
+    newValue: unknown
+  }
+  'node:slot-errors:changed': { nodeId: NodeId }
+  'node:slot-links:changed': {
+    nodeId: NodeId
+    slotType: NodeSlotType
+    slotIndex: number
+    connected: boolean
+    linkId: number
+  }
+  'node:slot-label:changed': {
+    nodeId: NodeId
+    slotType?: NodeSlotType
+  }
 }