feat(blog): add repository blog functionality

Adds comprehensive blog post system for repositories with draft/public/published status, featured images, tags, and subscriptions. Includes database models, migrations, CRUD operations, email notifications, explore page, and full UI templates for creating, editing, and viewing blog posts.

options/locale/locale_en-US.json

@@ -363,6 +363,7 @@
   "explore.users": "Users",
   "explore.organizations": "Organizations",
   "explore.packages": "Packages",
+  "explore.blogs": "Blogs",
   "explore.packages.empty.description": "No public or global packages are available yet.",
   "explore.go_to": "Go to",
   "explore.code": "Code",
@@ -491,6 +492,9 @@
   "mail.release.downloads": "Downloads:",
   "mail.release.download.zip": "Source Code (ZIP)",
   "mail.release.download.targz": "Source Code (TAR.GZ)",
+  "mail.blog.published_subject": "New blog post: \"%[1]s\" in %[2]s",
+  "mail.blog.published_body": "<b>@%[1]s</b> published a new blog post %[2]s in %[3]s",
+  "mail.blog.read_more": "Read More",
   "mail.repo.transfer.subject_to": "%s would like to transfer \"%s\" to %s",
   "mail.repo.transfer.subject_to_you": "%s would like to transfer \"%s\" to you",
   "mail.repo.transfer.to_you": "you",
@@ -1967,6 +1971,41 @@
   "repo.signing.wont_sign.not_signed_in": "You are not signed in.",
   "repo.ext_wiki": "Access to External Wiki",
   "repo.ext_wiki.desc": "Link to an external wiki.",
+  "repo.blog": "Blog",
+  "repo.blog.new": "New Post",
+  "repo.blog.edit": "Edit Post",
+  "repo.blog.delete": "Delete Post",
+  "repo.blog.delete_confirm": "Are you sure you want to delete this blog post?",
+  "repo.blog.title": "Title",
+  "repo.blog.subtitle": "Subtitle",
+  "repo.blog.content": "Content",
+  "repo.blog.tags": "Tags",
+  "repo.blog.tags_placeholder": "Comma-separated tags",
+  "repo.blog.featured_image": "Featured Image",
+  "repo.blog.status": "Status",
+  "repo.blog.draft": "Draft",
+  "repo.blog.public": "Public",
+  "repo.blog.published": "Published",
+  "repo.blog.save_draft": "Save Draft",
+  "repo.blog.save_public": "Save Public",
+  "repo.blog.publish": "Publish",
+  "repo.blog.subscribe": "Subscribe to Blog",
+  "repo.blog.unsubscribe": "Unsubscribe",
+  "repo.blog.subscribed": "Subscribed",
+  "repo.blog.no_posts": "No blog posts yet.",
+  "repo.blog.no_posts_member": "No blog posts yet. Create the first one!",
+  "repo.blog.featured": "Featured",
+  "repo.blog.read_more": "Read More",
+  "repo.blog.by_author": "by %s",
+  "repo.blog.published_notification": "%s published a new blog post: %s",
+  "repo.blog.featured_image_uuid": "Attachment UUID",
+  "repo.blog.featured_image_help": "Enter the UUID of an uploaded attachment to use as the featured image.",
+  "repo.blog.content_placeholder": "Write your blog post content here...",
+  "repo.blog.tags_help": "Separate tags with commas.",
+  "repo.settings.blog": "Blog",
+  "repo.settings.blog.enable": "Enable Blog",
+  "repo.settings.blog.enable_desc": "Allow blog posts to be created and published from this repository.",
+  "repo.settings.blog.saved": "Blog settings saved.",
   "repo.wiki": "Wiki",
   "repo.wiki.welcome": "Welcome to the Wiki.",
   "repo.wiki.welcome_desc": "The wiki lets you write and share documentation with collaborators.",
@@ -4001,6 +4040,8 @@
   "admin.config.hide_explore_button_desc": "Hide the Explore button from the header navigation bar",
   "admin.config.enable_explore_packages": "Enable Explore Packages",
   "admin.config.enable_explore_packages_desc": "Show a Packages tab in the Explore menu to browse public and global packages",
+  "admin.config.enable_blogs": "Enable Blogs",
+  "admin.config.enable_blogs_desc": "Enable the Blogs feature across the platform. Repos can publish blog posts visible under Explore > Blogs.",
   "admin.config.custom_home_title": "Homepage Title",
   "admin.config.custom_home_title_placeholder": "Leave empty to use app name",
   "admin.config.custom_home_title_help": "Custom title displayed on the homepage. Leave empty to use the default app name.",