[refactor] Migrate manager code to DDD structure (#5662)

## Summary

Reorganized custom nodes manager functionality from scattered technical
layers into a cohesive domain-focused module following [domain-driven
design](https://en.wikipedia.org/wiki/Domain-driven_design) principles.

## Changes

- **What**: Migrated all manager code from technical layers
(`src/components/`, `src/stores/`, etc.) to unified domain structure at
`src/workbench/extensions/manager/`
- **Breaking**: Import paths changed for all manager-related modules
(40+ files updated)

## Review Focus

Verify all import path updates are correct and no circular dependencies
introduced. Check that [Vue 3 composition
API](https://vuejs.org/guide/reusability/composables.html) patterns
remain consistent across relocated composables.


┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-5662-refactor-Migrate-manager-code-to-DDD-structure-2736d73d3650812c87faf6ed0fffb196)
by [Unito](https://www.unito.io)

src/components/dialog/content/manager/packBanner/PackBanner.vue

@@ -1,52 +0,0 @@
-<template>
-  <div class="w-full aspect-7/3 overflow-hidden">
-    <!-- default banner show -->
-    <div v-if="showDefaultBanner" class="w-full h-full">
-      <img
-        :src="DEFAULT_BANNER"
-        alt="default banner"
-        class="w-full h-full object-cover"
-      />
-    </div>
-    <!-- banner_url or icon show -->
-    <div v-else class="relative w-full h-full">
-      <!-- blur background -->
-      <div
-        v-if="imgSrc"
-        class="absolute inset-0 bg-cover bg-center bg-no-repeat opacity-30"
-        :style="{
-          backgroundImage: `url(${imgSrc})`,
-          filter: 'blur(10px)'
-        }"
-      ></div>
-      <!-- image -->
-      <img
-        :src="isImageError ? DEFAULT_BANNER : imgSrc"
-        :alt="nodePack.name + ' banner'"
-        :class="
-          isImageError
-            ? 'relative w-full h-full object-cover z-10'
-            : 'relative w-full h-full object-contain z-10'
-        "
-        @error="isImageError = true"
-      />
-    </div>
-  </div>
-</template>
-
-<script setup lang="ts">
-import { computed, ref } from 'vue'
-
-import type { components } from '@/types/comfyRegistryTypes'
-
-const DEFAULT_BANNER = '/assets/images/fallback-gradient-avatar.svg'
-
-const { nodePack } = defineProps<{
-  nodePack: components['schemas']['Node']
-}>()
-
-const isImageError = ref(false)
-
-const showDefaultBanner = computed(() => !nodePack.banner_url && !nodePack.icon)
-const imgSrc = computed(() => nodePack.banner_url || nodePack.icon)
-</script>