Remove yarn.lock file and fix dependencies

[six7]

removes yarn lock, seems we use npm

also fixes this issue that i got locally:

Uncaught Error: Incompatible React versions: The "react" and "react-dom" packages must have the exact same version. Instead got:
  - react:      19.2.0
  - react-dom:  19.1.1
Learn more: https://react.dev/warnings/version-mismatch
    at react-dom-client.development.js:24801:15
    at react-dom-client.development.js:24806:5
    at node_modules/react-dom/cjs/react-dom-client.development.js (react-dom-client.development.js:24993:3)
    at __require (chunk-PWLNVQY7.js?v=caf3680c:8:50)
    at node_modules/react-dom/client.js (client.js:37:20)
    at __require (chunk-PWLNVQY7.js?v=caf3680c:8:50)
    at react-dom_client.js:6:16

[Copilot]

Copilot wasn't able to review any files in this pull request.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.