Added endpoint to quickly render a snip. Also added a bit of image fetching

apps/fullstack/app/(unprotected)/schemas/page.tsx

apps/images/src/common/errorHandler.ts

apps/images/src/render/index.ts

apps/images/src/render/snip.ts

apps/images/src/server.ts

packages/python/src/snip/api/__init__.py

packages/python/src/snip/api/snippets.py

packages/python/tests/test_api.py

packages/render/src/backgrounds/index.ts