Use modern CSRF protection from stdlib #16747
Description
Please confirm
- I have searched existing issues to check if an issue already exists for my feature request.
Is your feature request related to a problem? Please describe.
LXD is now using Go 1.25 which comes with native CSRF protection.
Based on this blog, I think we could drop some custom code and leverage the builtin protection instead.
Describe the solution you'd like
Remove custom code and replace it with code from net/http to reduce the maintenance burden.
Describe alternatives you've considered
No response
Additional context
No response