Add a multi-page flags reference

Page link:

https://bazel.build/reference/command-line-reference

Problem description (include actual vs expected text, if applicable):

Currently the command-line-reference page has flags for every bazel subcommand. This makes using cmd+f a bit annoying since you can find flags that may not be applicable for the subcommand you're interested in, and there's no way to filter that out. I think having this page with all of them is fine, but I think there should also be a per-subcommand page to make this more scoped and easier to search through

Where do you see this issue? (include link to specific section of the page, if applicable)

No response

Any other information you'd like to share?

No response