nixf: ignoring annotations

[Aleksanaa]

Is your feature request related to a problem? Please describe.
Sometimes people need to keep some unused code for convenience reasons, or use other patterns that will throw warnings.

Describe the solution you'd like
Add a pattern in comments to escape some diagnostic messages.

# lint:ignore
foo = { ... };

If there is no content in this line except comments and spaces, ignore all diagnostic reports in the next line, otherwise ignore this line.

# lint:ignore=sema-unused-with,sema-escape-with

Ignore specific types of messages.

# lint:ignore=sema-unused-with:begin

# some code

# lint:ignore=sema-unused-with:end

Ignore code in between, and if no end was found, ignore till file ends.

Also add a command line flag to ignore the ignoring flag (😅)

Describe alternatives you've considered
Maybe there is still room for improvement in the design.

Additional context
NixOS/nixpkgs#331085