Display short help menu when --help is used

[zanieb]

I feel like I'm always drowning in the help output from uv because we have so many options.

I basically agree with the commentary in clap-rs/clap#4687 that having different behaviors for -h and --help is surprising. I think --help is more obvious for users and I want to optimize for that experience.

This roughly matches the help menus in Cargo and pip.

The uv help command can be used for long help. In #4906 and #4909 we improve that command.

Extends #4904 which adds test cases for the existing behavior.

[BurntSushi]

LGTM.

One other idea for "short" help information is to put the flag name and the help description on the same line, and then align the columns. For example, a selection from rg -h output:

  -i, --ignore-case               Case insensitive search.
  -v, --invert-match              Invert matching.
  -x, --line-regexp               Show matches surrounded by line boundaries.
  -m, --max-count=NUM             Limit the number of matching lines.
  --mmap                          Search with memory maps when possible.
  -U, --multiline                 Enable searching across multiple lines.
  --multiline-dotall              Make '.' match line terminators.
  --no-unicode                    Disable Unicode mode.
  --null-data                     Use NUL as a line terminator.
  -P, --pcre2                     Enable PCRE2 matching.
  --regex-size-limit=NUM          The size limit of the compiled regex.
  -S, --smart-case                Smart case search.
  --stop-on-nonmatch              Stop searching after a non-match.

This makes for very dense information display that is easy to read IMO.

The main drawback, I think, is that your descriptions have to be very short. But constraint inspires creativity. :-) And if there's a very long flag name, it can make the column alignment non-ideal. But if we can pull it off, I really like it personally.

(I am also a fan of the -h/--help distinction, but I in a sub-command architecture like we have with uv, I think command help ... is a very strong convention I've seen in many other places. So I think that's a great idea.)

[zanieb]

That'd be a nice format to explore — it'd require moving even further away from the clap defaults but I agree it'd be ideal for the short help display.