feat: add node replacement UI to Errors Tab (#9253)

## Summary

Adds a node replacement UI to the Errors Tab so users can swap missing
nodes with compatible alternatives directly from the error panel,
without opening a separate dialog.

## Changes

- **What**: New `SwapNodesCard` and `SwapNodeGroupRow` components render
swap groups in the Errors Tab; each group shows the missing node type,
its instances (with locate buttons), and a Replace button. Added
`useMissingNodeScan` composable to scan the graph for missing nodes and
populate `executionErrorStore`. Added `removeMissingNodesByType()` to
`executionErrorStore` so replaced nodes are pruned from the error list
reactively.

## Bug Fixes Found During Implementation

### Bug 1: Replaced nodes render as empty shells until page refresh

`replaceWithMapping()` directly mutates `_nodes[idx]`, bypassing the Vue
rendering pipeline entirely. Because the replacement node reuses the
same ID, `vueNodeData` retains the stale entry from the old placeholder
(`hasErrors: true`, empty widgets/inputs). `graph.setDirtyCanvas()` only
repaints the LiteGraph canvas and has no effect on Vue.

**Fix**: After `replaceWithMapping()`, manually call
`nodeGraph.onNodeAdded?.(newNode)` to trigger `handleNodeAdded` in
`useGraphNodeManager`, which runs `extractVueNodeData(newNode)` and
updates `vueNodeData` correctly. Also added a guard in `handleNodeAdded`
to skip `layoutStore.createNode()` when a layout for the same ID already
exists, preventing a duplicate `spatialIndex.insert()`.

### Bug 2: Missing node error list overwritten by incomplete server
response

Two compounding issues: (A) the server's `missing_node_type` error only
reports the *first* missing node — the old handler parsed this and
called `surfaceMissingNodes([singleNode])`, overwriting the full list
collected at load time. (B) `queuePrompt()` calls `clearAllErrors()`
before the API request; if the subsequent rescan used the stale
`has_errors` flag and found nothing, the missing nodes were permanently
lost.

**Fix**: Created `useMissingNodeScan.ts` which scans
`LiteGraph.registered_node_types` directly (not `has_errors`). The
`missing_node_type` catch block in `app.ts` now calls
`rescanAndSurfaceMissingNodes(this.rootGraph)` instead of parsing the
server's partial response.

## Review Focus

- `handleReplaceNode` removes the group from the store only when
`replaceNodesInPlace` returns at least one replaced node — should we
always clear, or only on full success?
- `useMissingNodeScan` re-scans on every execution-error change; confirm
no performance concerns for large graphs with many subgraphs.


## Screenshots 


https://github.com/user-attachments/assets/78310fc4-0424-4920-b369-cef60a123d50



https://github.com/user-attachments/assets/3d2fd5e1-5e85-4c20-86aa-8bf920e86987



┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-9253-feat-add-node-replacement-UI-to-Errors-Tab-3136d73d365081718d4ddfd628cb4449)
by [Unito](https://www.unito.io)

src/scripts/app.ts

@@ -79,12 +79,8 @@ import type { ComfyExtension, MissingNodeType } from '@/types/comfy'
 import type { ExtensionManager } from '@/types/extensionTypes'
 import type { NodeExecutionId } from '@/types/nodeIdentification'
 import { graphToPrompt } from '@/utils/executionUtil'
-import type { MissingNodeTypeExtraInfo } from '@/workbench/extensions/manager/types/missingNodeErrorTypes'
-import {
-  createMissingNodeTypeFromError,
-  getCnrIdFromNode,
-  getCnrIdFromProperties
-} from '@/workbench/extensions/manager/utils/missingNodeErrorUtil'
+import { getCnrIdFromProperties } from '@/workbench/extensions/manager/utils/missingNodeErrorUtil'
+import { rescanAndSurfaceMissingNodes } from '@/composables/useMissingNodeScan'
 import { anyItemOverlapsRect } from '@/utils/mathUtil'
 import {
   collectAllNodes,
@@ -1190,7 +1186,7 @@ export class ComfyApp {
     const embeddedModels: ModelFile[] = []
 
     const nodeReplacementStore = useNodeReplacementStore()
-
+    await nodeReplacementStore.load()
     const collectMissingNodesAndModels = (
       nodes: ComfyWorkflowJSON['nodes'],
       pathPrefix: string = '',
@@ -1527,35 +1523,8 @@ export class ComfyApp {
               typeof error.response.error === 'object' &&
               error.response.error?.type === 'missing_node_type'
             ) {
-              const extraInfo = (error.response.error.extra_info ??
-                {}) as MissingNodeTypeExtraInfo
-
-              let graphNode = null
-              if (extraInfo.node_id && this.rootGraph) {
-                graphNode = getNodeByExecutionId(
-                  this.rootGraph,
-                  extraInfo.node_id
-                )
-              }
-
-              const enrichedExtraInfo: MissingNodeTypeExtraInfo = {
-                ...extraInfo,
-                class_type: extraInfo.class_type ?? graphNode?.type,
-                node_title: extraInfo.node_title ?? graphNode?.title
-              }
-
-              const missingNodeType =
-                createMissingNodeTypeFromError(enrichedExtraInfo)
-
-              if (
-                graphNode &&
-                typeof missingNodeType !== 'string' &&
-                !missingNodeType.cnrId
-              ) {
-                missingNodeType.cnrId = getCnrIdFromNode(graphNode)
-              }
-
-              this.showMissingNodesError([missingNodeType])
+              // Re-scan the full graph instead of using the server's single-node response.
+              rescanAndSurfaceMissingNodes(this.rootGraph)
             } else if (
               !useSettingStore().get('Comfy.RightSidePanel.ShowErrorsTab') ||
               !(error instanceof PromptExecutionError)