add options and documentation for diagnostics

Some of my code has been untouched for quite some time, and thus, doesn't always follow the latest conventions, such as using short-hand struct initialization. I have a lot of code to maintain, and updating all of it to adhere to these conventions is very time consuming. This is generally why I avoid Clippy (among other reasons, like there being too many false positives), and also why I occasionally squash deprecation warnings.

It seems like rust-analyzer has its own lints that it provides, seemingly called "diagnostics" in the source code, but I cannot figure out how to disable them. In particular, I have some code that is not using shorthand struct initialization everywhere, so rust-analyzer warns at every such instance, which is quite annoying.

It took me quite some to figure out where this warning was coming from. At first, I thought rust-analyzer was somehow embedding Clippy. And then I thought perhaps the compiler was emitting this warning (strange as that might be) and that I had somehow squashed this warning in the normal cargo build workflow in a way that wasn't getting picked up by rust-analyzer.

It wasn't until I grepped the rust-analyzer source code that I realized it was the one responsible for the warning.

I was pretty surprised by this, and generally did not expect rust-analyzer to also be a linter. Is it intended for rust-analyzer to stand up its own linting strategies separate from Clippy?

It would be very nice to have some docs on this and also a way to turn it off. In particular, if I run cargo build in my terminal and that exits cleanly, then I generally expect rust-analyzer to be similarly clean.

Start by locating rust-analyzer's diagnostics in its source, especially the shorthand struct initialization warning mentioned in the report. Define the documentation and configuration behavior for disabling these diagnostics; done means users can understand their origin and turn them off when desired.