[High] Open GraphQL proxy: anyone with the URL could delete all tasks #73

What I liked

• Your token is not VITE_, so it's not in the browser bundle where anyone could read it. It stays on the server (vite.config.ts:27-41). I hadn't even thought about this for my own project.
• Filters live in the URL, so they survive a refresh and you can share them.

Problem

Any user's tasks could be deleted. In the worst case, someone with the URL deletes all tasks.

Root cause

api/graphql.ts forwards any request body and adds the token, but it doesn't check who is calling. You mention this risk in README.md:45.

Proposed fix

• Allow only requests from your own site (Origin check). This stops other websites, but not scripts like curl.
• Allow only the queries and mutations the app uses (allowlist). This is the stronger lock.

Acceptance criteria

• A request the app doesn't use is rejected.
• Normal app requests still work.