Admin view for assessing whether crates are empty

[carols10cents]

In dealing with reports of empty crates that are now against our policy, I'm now manually doing a bunch of clicking around and gathering info from a bunch of different sources, then either locking the account and deleting the crates if it appears the owner is only squatting, or emailing to see if the owner is still using the crates if the user has some legitimate usage of crates.io, according to our policies.

It would save me a ton of work if the info I needed for this task was on one-ish screen in the Prophesied Admin Interface of Dreams.

This page would be something like:

• crates.io/users/username/admin, so that I could still view the regular user page even when I'm in sudo mode
• display the user's verified email address so that I can email them if needed without needing to log in to the database
• list all crates, including those with all versions yanked (which the regular user page doesn't currently list), in a concise table format that contains the columns:
  • crate name
  • number of versions
  • publish date of most recent version
  • number of reverse dependencies (if the number is nonzero, link to the crate's /reverse_dependencies page so I can see if the dependencies are only this user's other crates)
  • link to docs.rs/crate/cratename/latest/source/lib.rs or main.rs so i can assess whether there's useful content or not
• sort by number of versions, low to high, then publish date earliest to latest
• ideally show all the user's crates without paging, realistically 50 on the page instead of 10 would probably be sufficient

just that would save a TON of time. bonus points:

• checkboxes that populate two markdown numbered list of crate names, one list of the checked names and one of the unchecked names. that is, if the table contains the crates foo, bar, and baz, and I tick the checkboxes for foo and baz, somewhere on the page are these two text lists I can copy:

1. foo
2. baz

1. bar

I'd like this functionality because in the emails I've been writing to people, I list out their empty crates that I want to know if they're still using, and I also list the crates of theirs that are fine and won't be deleted.