fix: stabilize promoted widget identity and fix link position on mode switch

Promoted widget rename propagation:
- Separate identity (name) from display (label) in PromotedWidgetView
  using a stable identityName (subgraphInput.name, e.g. "value_1")
- label getter/setter now reads/writes the bound subgraph slot directly
  via cached getBoundSubgraphSlot(), not widget state
- drawWidget uses this.label with try/finally for safe projected label
- SubgraphNode passes slotName through the reconcile pipeline as
  identityName; rename handler only changes input.label and _widget.label,
  preserving input.widget.name for matching
- renameWidget() no longer propagates to interior node widgets/inputs
- Vue label source changed from widget.slotName to widget.promotedLabel

Link position on draft restore:
- Call handleVueNodeLifecycleReset after initializeWorkflow so the node
  manager initializes against the fully-configured graph

Link position on legacy-to-Vue mode switch:
- Debounce layoutStore.onChange (800ms) to wait for all ResizeObserver
  measurement cycles to settle before resetting, with 3s fallback

src/composables/graph/useGraphNodeManager.ts

@@ -92,6 +92,10 @@ export interface SafeWidgetData {
    * execution ID (e.g. `"65:42"` vs the host node's `"65"`).
    */
   sourceExecutionId?: string
+  /** Tooltip text from the resolved widget. */
+  tooltip?: string
+  /** For promoted widgets, the display label from the subgraph input slot. */
+  promotedLabel?: string
 }
 
 export interface VueNodeData {
@@ -352,7 +356,8 @@ function safeWidgetMapper(
           sourceNode && app.rootGraph
             ? (getExecutionIdByNode(app.rootGraph, sourceNode) ?? undefined)
             : undefined,
-        tooltip: widget.tooltip
+        tooltip: widget.tooltip,
+        promotedLabel: isPromotedWidgetView(widget) ? widget.label : undefined
       }
     } catch (error) {
       console.warn(