fix(10): revise plans based on checker feedback

- Plan 10-02: Added explicit UserMailService wiring in Account.scala
  onRegister handler for activation emails when activateMode == User
- Plan 10-04: Split into backend-only (models, services, admin controller)
  reducing from 16 to 15 files, estimated context ~50%
- Plan 10-05: New plan for frontend components (Posts, Post, Categories,
  RelatedPosts), Wave 3 depends on 10-04
- Updated ROADMAP.md to reflect 5 plans for Phase 10

.planning/phases/10-core-plugins/10-04-PLAN.md

@@ -7,21 +7,21 @@ depends_on: ["10-03"]
 files_modified:
   - plugins/golem15/blog/models/Category.scala
   - plugins/golem15/blog/models/Tag.scala
+  - plugins/golem15/blog/models/PostCategory.scala
+  - plugins/golem15/blog/models/PostTag.scala
   - plugins/golem15/blog/repositories/CategoryRepository.scala
   - plugins/golem15/blog/repositories/TagRepository.scala
   - plugins/golem15/blog/services/CategoryService.scala
   - plugins/golem15/blog/services/TagService.scala
+  - plugins/golem15/blog/services/NestedTree.scala
   - plugins/golem15/blog/services/BlogPostService.scala
+  - plugins/golem15/blog/repositories/BlogPostRepository.scala
+  - plugins/golem15/blog/controllers/Posts.scala
   - plugins/golem15/blog/controllers/Categories.scala
-  - plugins/golem15/blog/components/Posts.scala
-  - plugins/golem15/blog/components/Post.scala
-  - plugins/golem15/blog/components/Categories.scala
-  - plugins/golem15/blog/components/RelatedPosts.scala
   - plugins/golem15/blog/resources/db/migration/V10_2_2__blog_categories_tags.sql
+  - plugins/golem15/blog/resources/controllers/posts/fields.yaml
   - plugins/golem15/blog/resources/controllers/categories/fields.yaml
-  - plugins/golem15/blog/resources/views/posts/default.peb
-  - plugins/golem15/blog/resources/views/posts/item.peb
-  - plugins/golem15/blog/resources/views/post/default.peb
+  - plugins/golem15/blog/resources/controllers/categories/columns.yaml
 autonomous: true
 
 must_haves:
@@ -29,9 +29,8 @@ must_haves:
     - "Blog posts can be assigned to categories"
     - "Categories are hierarchical (parent/child)"
     - "Blog posts can have multiple tags"
-    - "Frontend displays post listings with pagination"
-    - "Frontend displays individual post pages"
-    - "Related posts shown based on shared categories/tags"
+    - "Admin can manage categories in tree view"
+    - "Related posts calculated by shared categories/tags"
   artifacts:
     - path: "plugins/golem15/blog/models/Category.scala"
       provides: "Hierarchical category model with nested set"
@@ -39,20 +38,16 @@ must_haves:
     - path: "plugins/golem15/blog/models/Tag.scala"
       provides: "Tag model for free-form labeling"
       contains: "case class Tag"
-    - path: "plugins/golem15/blog/components/Posts.scala"
-      provides: "Frontend post listing component"
-      exports: ["PostsComponent", "onLoadMore"]
-    - path: "plugins/golem15/blog/components/Post.scala"
-      provides: "Single post display component"
-      exports: ["PostComponent"]
+    - path: "plugins/golem15/blog/services/CategoryService.scala"
+      provides: "Category CRUD with tree operations"
+      exports: ["CategoryService", "getTree", "getAllChildrenAndSelf"]
+    - path: "plugins/golem15/blog/controllers/Categories.scala"
+      provides: "Admin controller for category management"
+      exports: ["CategoriesController"]
     - path: "plugins/golem15/blog/resources/db/migration/V10_2_2__blog_categories_tags.sql"
       provides: "Categories, tags, and pivot tables"
       contains: "CREATE TABLE blog_categories"
   key_links:
-    - from: "plugins/golem15/blog/components/Posts.scala"
-      to: "BlogPostService"
-      via: "post listing"
-      pattern: "postService\\.listFrontend"
     - from: "plugins/golem15/blog/services/BlogPostService.scala"
       to: "CategoryService"
       via: "category filtering"
@@ -61,19 +56,23 @@ must_haves:
       to: "NestedTree"
       via: "tree operations"
       pattern: "NestedTree\\."
+    - from: "plugins/golem15/blog/controllers/Categories.scala"
+      to: "CategoryService"
+      via: "CRUD operations"
+      pattern: "categoryService\\."
 ---
 
 <objective>
-Complete the Blog plugin with categories, tags, and frontend listing components.
+Add categories and tags to the Blog plugin with admin management.
 
-Purpose: Enable content organization and frontend display, demonstrating hierarchical data structures and frontend component patterns.
+Purpose: Enable content organization with hierarchical categories and free-form tags, providing the data layer for frontend components.
 
-Output: Complete Blog plugin with:
+Output: Blog plugin extended with:
 - Hierarchical categories using nested set model
 - Tags for free-form labeling
-- Frontend Posts component with pagination/infinite scroll
-- Frontend Post component for single post display
-- Related posts based on shared categories/tags
+- Admin controller for category management
+- BlogPostService updated with category/tag relations
+- Related posts algorithm based on shared categories/tags
 </objective>
 
 <execution_context>
@@ -91,7 +90,7 @@ Output: Complete Blog plugin with:
 # Prior plan in this phase
 @.planning/phases/10-core-plugins/10-03-SUMMARY.md
 
-# Reference: Phase 3 component patterns for HTMX
+# Reference: Phase 7 admin controller patterns
 </context>
 
 <tasks>
@@ -209,7 +208,7 @@ Output: Complete Blog plugin with:
 </task>
 
 <task type="auto">
-  <name>Task 2: Update BlogPostService for relations</name>
+  <name>Task 2: Update BlogPostService and admin for relations</name>
   <files>
     plugins/golem15/blog/services/BlogPostService.scala (modify)
     plugins/golem15/blog/repositories/BlogPostRepository.scala (modify)
@@ -340,150 +339,6 @@ Output: Complete Blog plugin with:
   </done>
 </task>
 
-<task type="auto">
-  <name>Task 3: Frontend listing components</name>
-  <files>
-    plugins/golem15/blog/components/Posts.scala
-    plugins/golem15/blog/components/Post.scala
-    plugins/golem15/blog/components/Categories.scala
-    plugins/golem15/blog/components/RelatedPosts.scala
-    plugins/golem15/blog/resources/views/posts/default.peb
-    plugins/golem15/blog/resources/views/posts/item.peb
-    plugins/golem15/blog/resources/views/post/default.peb
-    plugins/golem15/blog/resources/views/categories/default.peb
-    plugins/golem15/blog/resources/views/relatedposts/default.peb
-    plugins/golem15/blog/Plugin.scala (modify)
-  </files>
-  <action>
-    Create frontend components for blog display:
-
-    **Posts.scala (research Pattern 8):**
-    - Extend SummerComponent trait
-    - ComponentDetails: name "Posts", description "Blog post listing"
-    - Property schema:
-      - pageNumber: String, URL param for pagination, default "{{ :page }}"
-      - categoryFilter: String, filter by category slug
-      - postsPerPage: String, default "10", validation 1-100
-      - noPostsMessage: String, default "No posts found."
-      - sortOrder: Dropdown with BlogPost.allowedSortingOptions
-      - throwNotFound: Checkbox, 404 on empty results
-    - Page variables: posts (PaginatedResult), category (Option), noPostsMessage
-    - onRun lifecycle:
-      - Load category if categoryFilter set
-      - Build PostListOptions from properties
-      - Call postService.listFrontend or listByCategory
-      - Handle empty results per throwNotFound
-      - Set page context variables
-    - onLoadMore HTMX handler:
-      - Parse page number from form
-      - Load next page of posts
-      - Return items partial
-      - Trigger "postsExhausted" when no more
-
-    **Post.scala component:**
-    - ComponentDetails: name "Post", description "Single post display"
-    - Property schema:
-      - slug: String, URL param for post slug, default "{{ :slug }}"
-      - notFoundMessage: String
-    - Page variables: post (BlogPostWithRelations)
-    - onRun lifecycle:
-      - Get slug from URL
-      - Call postService.findBySlug
-      - 404 if not found
-      - Set page context: post, author, categories, tags, readingTime
-      - Set OpenGraph meta tags for social sharing
-
-    **Categories.scala component:**
-    - ComponentDetails: name "Categories", description "Category listing/tree"
-    - Property schema:
-      - displayMode: Dropdown (tree/flat), default "tree"
-      - showPostCount: Checkbox, default true
-      - includeEmpty: Checkbox, show categories with no posts
-    - Page variables: categories (tree or flat list)
-    - onRun: Load category tree, filter empty if needed
-
-    **RelatedPosts.scala component:**
-    - ComponentDetails: name "RelatedPosts", description "Related posts by category/tag"
-    - Property schema:
-      - limit: String, max posts to show, default "3"
-      - postSlug: String, current post slug (from context)
-    - Page variables: relatedPosts (List)
-    - onRun: Call postService.getRelatedPosts, set context
-
-    **Templates:**
-
-    **posts/default.peb (research code example):**
-    ```html
-    <div class="blog-posts" id="posts-{{ __SELF__ }}">
-      {% if posts.items is empty %}
-        <div class="no-posts">{{ noPostsMessage }}</div>
-      {% else %}
-        <div class="posts-list">
-          {% for post in posts.items %}
-            {% include "posts/item" %}
-          {% endfor %}
-        </div>
-
-        {% if posts.hasNext %}
-          <div class="load-more">
-            <button
-              hx-post="{{ componentHandler('onLoadMore') }}"
-              hx-vals='{"page": {{ posts.currentPage + 1 }}}'
-              hx-target="#posts-{{ __SELF__ }} .posts-list"
-              hx-swap="beforeend"
-              hx-indicator=".htmx-indicator">
-              Load More
-              <span class="htmx-indicator">Loading...</span>
-            </button>
-          </div>
-        {% endif %}
-      {% endif %}
-    </div>
-    ```
-
-    **posts/item.peb:**
-    - Article element with post data
-    - Featured image (lazy load)
-    - Title as link to post page
-    - Excerpt or auto-generated summary
-    - Author name, published date, reading time
-    - Category and tag links
-
-    **post/default.peb:**
-    - Full post display
-    - OpenGraph meta tags in head
-    - Title, featured image, author, date
-    - Content HTML
-    - Categories and tags
-    - Share buttons (copy link, Twitter, Facebook)
-    - Include RelatedPosts component placeholder
-
-    **categories/default.peb:**
-    - Tree or flat list based on displayMode
-    - Category name as link
-    - Post count if showPostCount
-
-    **relatedposts/default.peb:**
-    - Grid of related post cards
-    - Image, title, excerpt snippet
-
-    **Register all components in Plugin.scala boot method**
-  </action>
-  <verify>
-    ./mill summercms.compile succeeds
-    Components registered in Plugin.scala
-    Templates have valid Pebble syntax
-    HTMX attributes properly formatted
-  </verify>
-  <done>
-    Posts component displays paginated listings with infinite scroll.
-    Post component displays single post with meta tags.
-    Categories component shows category tree/list.
-    RelatedPosts component shows related content.
-    All templates render with HTMX interactions.
-  </done>
-</task>
-
 </tasks>
 
 <verification>
@@ -491,9 +346,8 @@ After all tasks complete:
 1. Blog plugin compiles: `./mill summercms.compile`
 2. Migration creates all tables: blog_categories, blog_tags, pivot tables
 3. Category nested tree rebuilds correctly on insert/delete
-4. Posts component loads and paginates
-5. Post component displays with OpenGraph meta
-6. Related posts algorithm returns relevant content
+4. Posts admin form shows category tree selector and tag input
+5. Related posts algorithm returns relevant content
 </verification>
 
 <success_criteria>
@@ -501,10 +355,8 @@ After all tasks complete:
 - Nested set left/right values correct after operations
 - Tags can be created on-the-fly when typing
 - Post admin form shows category tree selector and tag input
-- Frontend /blog shows post listing with load more
-- Frontend /blog/:slug shows full post with related posts
-- Category pages filter posts by category and children
-- Tag pages filter posts by tag
+- Admin can manage categories with tree view and drag-drop
+- Related posts calculated by shared categories/tags
 </success_criteria>
 
 <output>