refactor: remove legacy missing nodes dialog (#10102)

## Summary

- Remove the legacy missing nodes modal dialog and migrate all
functionality to the existing Error Overlay / TabErrors system
- Migrate core node version warning from `MissingCoreNodesMessage.vue`
to `MissingNodeCard` in the errors tab
- Remove `Comfy.Workflow.ShowMissingNodesWarning` setting (errors tab
always surfaces missing nodes)
- Delete 6 legacy files: `useMissingNodesDialog.ts`,
`MissingNodesContent.vue`, `MissingNodesFooter.vue`,
`MissingNodesHeader.vue`, `MissingCoreNodesMessage.vue` and its test
- Rename `showMissingNodesDialog`/`showMissingModelsDialog` params to
`showMissingNodes`/`showMissingModels`
- Add `errorOverlay` and `missingNodeCard` to centralized `TestIds`
- Migrate all E2E tests from legacy dialog selectors to error overlay
testIds
- Add new E2E test: MissingNodeCard visible via "See Errors" button flow
- Add new E2E test: subgraph missing node type verified by expanding
pack row
- Add `surfaceMissingNodes` unit tests to `executionErrorStore`
- Guard `semver.compare` against invalid version strings
- Add `role="alert"`, `aria-hidden` for accessibility
- Use reactive props destructuring in `MissingNodeCard` and
`MissingPackGroupRow`

**Net change: -669 lines** (19 files, +323 / -992)


<img width="733" height="579" alt="image"
src="https://github.com/user-attachments/assets/c497809d-b176-43bf-9872-34bd74c6ea0d"
/>


## Test plan

- [x] Unit tests: MissingNodeCard core node warning (7 tests)
- [x] Unit tests: surfaceMissingNodes (4 tests)
- [x] Unit tests: workflowService showPendingWarnings (updated)
- [x] E2E: Error overlay visible on missing nodes workflow
- [x] E2E: Error overlay visible on subgraph missing nodes
- [x] E2E: MissingNodeCard visible via See Errors button
- [x] E2E: Subgraph node type visible after expanding pack row
- [x] E2E: Error overlay does not resurface on undo/redo
- [x] E2E: Error overlay does not reappear on workflow tab switch
- [x] Typecheck, lint, knip all passing

## Related issues

- Closes #9923 (partially — `errorOverlay` and `missingNodeCard` added
to TestIds)
- References #10027 (mock hoisting inconsistency)
- References #10033 (i18n-based test selectors)
- References #10085 (DDD layer violation + focusedErrorNodeId)

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-10102-refactor-remove-legacy-missing-nodes-dialog-3256d73d365081c194d2e90bc6401846)
by [Unito](https://www.unito.io)

browser_tests/tests/sidebar/workflows.spec.ts

@@ -1,6 +1,7 @@
 import { expect } from '@playwright/test'
 
 import { comfyPageFixture as test } from '../../fixtures/ComfyPage'
+import { TestIds } from '../../fixtures/selectors'
 
 test.describe('Workflows sidebar', () => {
   test.beforeEach(async ({ comfyPage }) => {
@@ -234,23 +235,29 @@ test.describe('Workflows sidebar', () => {
   test('Does not report warning when switching between opened workflows', async ({
     comfyPage
   }) => {
+    await comfyPage.settings.setSetting(
+      'Comfy.RightSidePanel.ShowErrorsTab',
+      true
+    )
     await comfyPage.workflow.loadWorkflow('missing/missing_nodes')
-    await comfyPage.page
-      .locator('.p-dialog')
-      .getByRole('button', { name: 'Close' })
-      .click({ force: true })
-    await comfyPage.page.locator('.p-dialog').waitFor({ state: 'hidden' })
+
+    const errorOverlay = comfyPage.page.getByTestId(
+      TestIds.dialogs.errorOverlay
+    )
+    await expect(errorOverlay).toBeVisible()
+
+    // Dismiss the error overlay
+    await errorOverlay.getByRole('button', { name: 'Dismiss' }).click()
+    await expect(errorOverlay).not.toBeVisible()
 
     // Load blank workflow
     await comfyPage.menu.workflowsTab.open()
     await comfyPage.command.executeCommand('Comfy.NewBlankWorkflow')
 
-    // Switch back to the missing_nodes workflow
+    // Switch back to the missing_nodes workflow — overlay should not reappear
     await comfyPage.menu.workflowsTab.switchToWorkflow('missing_nodes')
 
-    await expect(
-      comfyPage.page.locator('.comfy-missing-nodes')
-    ).not.toBeVisible()
+    await expect(errorOverlay).not.toBeVisible()
   })
 
   test('Can close saved-workflows from the open workflows section', async ({