feat: show reset dialog box when user not found in DB

[xrvnd]

Changes

Backend

• Added validateUser() helper function in src/services/user/user.ts that checks DB if user exists
• All puzzle API routes (/status, /hint, /check) now call validateUser before processing and returns 404 { error: "USER_NOT_FOUND" } if not found

Frontend

• Axios response interceptor maps 404 USER_NOT_FOUND to regular Error("USER_NOT_FOUND") so we can differentiate errors
• New UserResetDialog component overlays the game with an "Account not found" message and a Reset button, clicking it removes userId from localStorage and reloads the page
• Fixed a pre existing bug: toast.error was being called during render in Daily page; lifted it to a useEffect

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How to test/ Testing screenshots

Insert a fakeuser with a userId in the console.

Reload the /daily page and the reset dialog should appear. Click on Reset here.

localStorage.userId is cleared in the local storage

Closes #37

[vercel]

@xrvnd is attempting to deploy a commit to the coderzs' projects Team on Vercel.

A member of the Team first needs to authorize it.

[coder-zs-cse]

Can u resolve merge conflicts. Also can we habe our puzzle theme for the dialog box colors

[xrvnd]

Will get on this and push a fix

[xrvnd]

PR is ready to review and merge.

Thought this would be a nice theme for the dialog box, let me know if we align on this. Or if you have something specific in mind I'll make those changes as well.

[xrvnd]

@coder-zs-cse review please :)

[xrvnd]

hi @coder-zs-cse , bro review plis

[xrvnd]

@coder-zs-cse review please