feat: initialize blog app with blueprints and templates

Extract blog-specific code from the coop monolith into a standalone
repository. Includes auth, blog, post, admin, menu_items, snippets
blueprints, associated templates, Dockerfile (APP_MODULE=app:app),
entrypoint, and Gitea CI workflow.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

README.md

@@ -0,0 +1,60 @@
+# Blog App
+
+Blog and content management application for the Rose Ash cooperative platform.
+
+## Overview
+
+This is the **blog** service extracted from the Rose Ash (Suma Browser) monolith.
+It handles:
+
+- **Blog**: Ghost CMS integration for browsing, creating, and editing posts
+- **Auth**: Magic link authentication and user account management
+- **Admin/Settings**: Administrative interface and settings management
+- **Menu Items**: Navigation menu item management
+- **Snippets**: Reusable content snippet management
+- **Internal API**: Server-to-server endpoints for cross-app data sharing
+
+## Tech Stack
+
+- **Quart** (async Flask) with HTMX
+- **SQLAlchemy 2.0** (async) with PostgreSQL
+- **Redis** for page caching
+- **Ghost CMS** for blog content
+
+## Running
+
+```bash
+# Set environment variables (see .env.example)
+export APP_MODULE=app:app
+
+# Run migrations
+alembic upgrade head
+
+# Start the server
+hypercorn app:app --bind 0.0.0.0:8000
+```
+
+## Docker
+
+```bash
+docker build -t blog .
+docker run -p 8000:8000 --env-file .env blog
+```
+
+## Directory Structure
+
+```
+app.py              # Application factory and entry point
+bp/                 # Blueprints
+  auth/             # Authentication (magic links, account)
+  blog/             # Blog listing, Ghost CMS integration
+  post/             # Individual post viewing and admin
+  admin/            # Settings admin interface
+  menu_items/       # Navigation menu management
+  snippets/         # Content snippet management
+  coop_api.py       # Internal API endpoints
+templates/          # Jinja2 templates
+  _types/           # Feature-specific templates
+entrypoint.sh       # Docker entrypoint (migrations + server start)
+Dockerfile          # Container build definition
+```