Add FastAPI web/API layer and static site

- queries.py: shared read-only query helpers (feed, brief, category counts)
  returning plain dicts, used by the API and available to the CLI.
- api.py: FastAPI service with Pydantic response models (the companion-app
  contract), CORS, and endpoints for categories, feed, brief, and health;
  mounts a static site at /.
- static/index.html: minimal dependency-free site rendering the daily five
  and topic/flavor category browsing.
- 'goodnews serve' command launches uvicorn (lazy import; core CLI stays
  pure-stdlib). Web deps live behind the optional [web] extra.
- Dockerfile + .dockerignore + build-system metadata so the service installs
  and deploys cleanly, with the DB mounted as a shared volume.
- README: web/API and deployment docs.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

goodnews/cli.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import argparse
+import os
 import sqlite3
 from pathlib import Path
 
@@ -71,7 +72,17 @@ def main() -> None:
     show_brief_parser.add_argument("--date", help="Brief date in YYYY-MM-DD format; defaults to latest brief")
     show_brief_parser.add_argument("--limit", type=int, default=10)
 
+    serve_parser = subparsers.add_parser("serve", help="Run the web/API server (requires the 'web' extra)")
+    serve_parser.add_argument("--host", default="127.0.0.1", help="Bind host; use 0.0.0.0 to expose")
+    serve_parser.add_argument("--port", type=int, default=8000)
+    serve_parser.add_argument("--reload", action="store_true", help="Auto-reload on code changes (dev)")
+
     args = parser.parse_args()
+
+    if args.command == "serve":
+        serve(args)
+        return
+
     conn = connect(args.db)
 
     if args.command == "init-db":
@@ -190,6 +201,20 @@ def list_recent(conn: sqlite3.Connection, limit: int, accepted_only: bool) -> No
         print(f"  {row['canonical_url']}")
 
 
+def serve(args: argparse.Namespace) -> None:
+    try:
+        import uvicorn
+    except ModuleNotFoundError:
+        raise SystemExit(
+            "The web server needs the optional 'web' extra. Install it with:\n"
+            "  pip install -e '.[web]'"
+        )
+    # Make sure the API reads the same database the CLI was pointed at.
+    os.environ.setdefault("GOODNEWS_DB", str(args.db))
+    print(f"Serving goodNews on http://{args.host}:{args.port}  (docs at /docs)")
+    uvicorn.run("goodnews.api:app", host=args.host, port=args.port, reload=args.reload)
+
+
 def list_category(
     conn: sqlite3.Connection,
     topic: str | None,