chore(docker): compose, entrypoint guard, LF shell script; format with Prettier

- Add docker-compose.yml (build context .) and .gitattributes for entrypoint LF
- README: document docker compose and gregWiki root requirement
- package.json: include docker-compose.yml in npm run format

Made-with: Cursor

docker-compose.yml

@@ -0,0 +1,11 @@
+# Run from this directory (gregWiki repo root):  docker compose up --build
+# Wrong context (e.g. monorepo parent) causes: ENOENT /app/package.json
+services:
+  wiki:
+    build:
+      context: .
+      dockerfile: Dockerfile
+    ports:
+      - '3000:3000'
+    environment:
+      CHOKIDAR_USEPOLLING: 'true'