feat: email change UI, Swagger UI improvements, key recovery link on landing page

- Email change modal: API key + new email → verification code → confirmed
- Swagger UI with proper OpenAPI spec (public/openapi.json + swagger-ui assets)
- Key recovery link prominently on landing page hero section
- Footer link for email change
- Updated docs.html to use swagger-ui bundle

docker-compose.yml

@@ -18,8 +18,8 @@ services:
       - SMTP_HOST=host.docker.internal
       - SMTP_PORT=25
       - POOL_SIZE=15
-      - BROWSER_COUNT=2
-      - PAGES_PER_BROWSER=8
+      - BROWSER_COUNT=1
+      - PAGES_PER_BROWSER=15
     volumes:
       - docfast-data:/app/data
     mem_limit: 2560m