feat: add display name mappings for Essentials tab nodes (#9072)

## Summary

Add frontend-only display name mappings for nodes shown in the
Essentials tab, plus parse the new `essentials_category` field from the
backend.

## Changes

- **What**: Created `src/constants/essentialsDisplayNames.ts` with a
static mapping of node names to user-friendly display names (e.g.
`CLIPTextEncode` → "Text", `ImageScale` → "Resize Image"). Regular nodes
use exact name matching; blueprint nodes use prefix matching since their
filenames include model-specific suffixes. Integrated into
`NodeLibrarySidebarTab.vue`'s `renderedRoot` computed for leaf node
labels with fallback to `display_name`. Added `essentials_category`
(z.string().optional()) to the node def schema and `ComfyNodeDefImpl` to
parse the field already sent by the backend (PR #12357).

## Review Focus

Display names are resolved only in the Essentials tab tree view
(`NodeLibrarySidebarTab.vue`), not globally, to avoid side effects on
search, bookmarks, or other views. Blueprint prefix matching is ordered
longest-first so more specific prefixes (e.g. `image_inpainting_`) match
before shorter ones (e.g. `image_edit`).

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-9072-feat-add-display-name-mappings-for-Essentials-tab-nodes-30f6d73d3650817c9acdc9b0315ed0be)
by [Unito](https://www.unito.io)

src/components/sidebar/tabs/NodeLibrarySidebarTab.vue

@@ -154,6 +154,7 @@ import {
   render
 } from 'vue'
 
+import { resolveEssentialsDisplayName } from '@/constants/essentialsDisplayNames'
 import SearchBox from '@/components/common/SearchBox.vue'
 import type { SearchFilter } from '@/components/common/SearchFilterChip.vue'
 import TreeExplorer from '@/components/common/TreeExplorer.vue'
@@ -276,7 +277,9 @@ const renderedRoot = computed<TreeExplorerNode<ComfyNodeDefImpl>>(() => {
 
     return {
       key: node.key,
-      label: node.leaf ? node.data.display_name : node.label,
+      label: node.leaf
+        ? (resolveEssentialsDisplayName(node.data) ?? node.data.display_name)
+        : node.label,
       leaf: node.leaf,
       data: node.data,
       getIcon() {