fix: disable window resizing

[Huderon]

Summary

fix for #422

Disables window resizing

Type of change

• Bug fix
• New feature / behavior change
• UI / component change (frontend)
• Backend / installer logic (Go)
• Build / release / CI
• Refactor (no behavior change)
• Documentation
• Other:

Testing

• bun run check passes (frontend, from frontend/)
• bun run lint passes (frontend, from frontend/)
• bun run test passes (frontend, from frontend/)
• go test ./... passes (backend)

AI disclosure

• I did not use AI assistance for this PR
• I used AI assistance and personally reviewed all generated output before submitting
• An AI agent generated part or all of this PR with minimal personal review. Details:

[Huderon]

Didn't realise it was an option, but zooming is also busted. There doesn't appear to be an option to disable zoom for Mac or Linux, not sure if it's an issue there.

Ideally we fix frontend scaling, but this should suffice short term.