Add more analyzer coverage for coding style guidelines

Not all of our coding style guidelines are covered by analyzers. https://github.com/dotnet/winforms/blob/main/docs/coding-style.md Some things that currently aren't covered:

- XML comments indented by a space
- Line breaks start with operators: `||` at the beginning of the line for example
- `=>` stays on the previous line (for better alignment of further line breaks)
- `t_` for thread statics
- `unsafe` on methods or classes only
- No empty XML comment blocks
- `=` can be aligned in some cases
- `?:` should be on a single line or broken starting two lines with `?` and `:`