feat(blog): add series support and v2 API endpoints

Adds blog series field to group related posts together. Implements v2 API endpoints for listing, creating, updating, and deleting blog posts with proper error codes. Adds series filtering to explore page and sitemap support with pagination. Includes BlogPostV2 structs with author/repo references, HTML URLs, and content rendering. Updates editor UI with series input field.

modules/errors/codes.go

@@ -157,6 +157,12 @@ const (
 	WikiDisabled          ErrorCode = "WIKI_DISABLED"
 )
 
+// Blog errors (BLOG_)
+const (
+	BlogPostNotFound ErrorCode = "BLOG_POST_NOT_FOUND"
+	BlogDisabled     ErrorCode = "BLOG_DISABLED"
+)
+
 // errorInfo contains metadata about an error code
 type errorInfo struct {
 	Message    string
@@ -277,6 +283,10 @@ var errorCatalog = map[ErrorCode]errorInfo{
 	WikiPageAlreadyExists: {"Wiki page already exists", http.StatusConflict},
 	WikiReservedName:      {"Wiki page name is reserved", http.StatusBadRequest},
 	WikiDisabled:          {"Wiki is disabled for this repository", http.StatusForbidden},
+
+	// Blog errors
+	BlogPostNotFound: {"Blog post not found", http.StatusNotFound},
+	BlogDisabled:     {"Blogs are disabled", http.StatusForbidden},
 }
 
 // Message returns the human-readable message for an error code

modules/structs/repo_blog_v2.go

@@ -0,0 +1,72 @@
+// Copyright 2026 MarketAlly. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package structs
+
+import "time"
+
+// BlogPostV2 represents a blog post in v2 API format
+type BlogPostV2 struct {
+	ID               int64          `json:"id"`
+	Title            string         `json:"title"`
+	Subtitle         string         `json:"subtitle,omitempty"`
+	Series           string         `json:"series,omitempty"`
+	Content          string         `json:"content,omitempty"`
+	ContentHTML      string         `json:"content_html,omitempty"`
+	Tags             []string       `json:"tags"`
+	Status           string         `json:"status"`
+	AllowComments    bool           `json:"allow_comments"`
+	FeaturedImageURL string         `json:"featured_image_url,omitempty"`
+	Author           *BlogAuthorV2  `json:"author,omitempty"`
+	Repo             *BlogRepoRefV2 `json:"repo,omitempty"`
+	CreatedAt        time.Time      `json:"created_at"`
+	UpdatedAt        time.Time      `json:"updated_at"`
+	PublishedAt      *time.Time     `json:"published_at,omitempty"`
+	HTMLURL          string         `json:"html_url"`
+}
+
+// BlogAuthorV2 represents the author of a blog post
+type BlogAuthorV2 struct {
+	ID        int64  `json:"id"`
+	Username  string `json:"username"`
+	Name      string `json:"name"`
+	AvatarURL string `json:"avatar_url"`
+}
+
+// BlogRepoRefV2 is a minimal repo reference in blog responses
+type BlogRepoRefV2 struct {
+	ID       int64  `json:"id"`
+	FullName string `json:"full_name"`
+	HTMLURL  string `json:"html_url"`
+}
+
+// BlogPostListV2 represents a paginated list of blog posts
+type BlogPostListV2 struct {
+	Posts      []*BlogPostV2 `json:"posts"`
+	TotalCount int64         `json:"total_count"`
+	HasMore    bool          `json:"has_more"`
+}
+
+// CreateBlogPostV2Option represents options for creating a blog post
+type CreateBlogPostV2Option struct {
+	Title             string   `json:"title" binding:"Required;MaxSize(255)"`
+	Subtitle          string   `json:"subtitle" binding:"MaxSize(500)"`
+	Series            string   `json:"series" binding:"MaxSize(255)"`
+	Content           string   `json:"content" binding:"Required"`
+	Tags              []string `json:"tags"`
+	Status            string   `json:"status"` // draft, public, published
+	AllowComments     bool     `json:"allow_comments"`
+	FeaturedImageUUID string   `json:"featured_image_uuid"`
+}
+
+// UpdateBlogPostV2Option represents options for updating a blog post
+type UpdateBlogPostV2Option struct {
+	Title             *string  `json:"title" binding:"MaxSize(255)"`
+	Subtitle          *string  `json:"subtitle" binding:"MaxSize(500)"`
+	Series            *string  `json:"series" binding:"MaxSize(255)"`
+	Content           *string  `json:"content"`
+	Tags              []string `json:"tags"`
+	Status            *string  `json:"status"` // draft, public, published
+	AllowComments     *bool    `json:"allow_comments"`
+	FeaturedImageUUID *string  `json:"featured_image_uuid"`
+}