Refactor to clap-4 with derive

[TD-Sky]

The construction of CLI

Use clap-4.0.18 with derive feature.

The only way I know to reserve the old style of help information which mimicked fzf is using Command::override_help with the help information written manually.

I write help for every argument and then modify the auto generated help information to get the final one.

To developers:

1. crate::cli::Cli could parse string to type value(s) now, so it's no need to parse string in succeeding functions.

2. These enums of arguments implementing ValueEnum,

   • crate::engine::fuzzy::FuzzyAlgorithm
   • crate::item::RankCriteria
   • crate::CaseMatching
   • And new enum crate::Layout

3. Some fields of crate::options::SkimOptions change types,

   • expect: Option<&str> => Vec<&str>
   • tiebreak: Option<String> => Vec<RankCriteria>
   • delimiter: Option<&str> => &str
   • color: Option<&str> => Vec<&str>
   • margin: Option<&str> => Vec<&str>
   • tabstop: Option<&str> => Option<usize>
   • layout: &'a str => Layout

4. For the above reasons, the ways to use SkimOptions change,

   • In crate::input::Input,

     • Before: parse_expect_keys(&mut self, keys: Option<&str>)
     • Now: parse_expect_keys(&mut self, keys: &[&str])

   • In crate::item, remove parse_criteria;

   • In crate::theme::ColorTheme,

     • Before: from_options(color: &str) -> Self
     • Now: from_options(color: &[&str]) -> Self

   • In crate::util,

     • Before: parse_margin(margins: &str) -> (Size, Size, Size, Size)
     • Now: parse_margin(margins: &[&str]) -> (Size, Size, Size, Size)

   • See crate::header::with_options, crate::model, crate::selection;

To users of library

In skim::prelude::SkimOptionsBuilder

• layout:
  • Before: layout(&mut self, value: &'a str) -> &mut Self
  • Now: layout(&mut self, value: skim::Layout) -> &mut Self

In skim::prelude::SkimItemReaderOption

• nth:

  • Before: nth(self, nth: &str) -> Self
  • Now: nth(self, nth: I) -> Self

• with_nth:

  • Before: with_nth(self, with_nth: &str) -> Self
  • Now: with_nth(self, with_nth: I) -> Self

[TD-Sky]

It maybe quite a long time that this PR can't be completed because of the issue#4501 in clap.

[TD-Sky]

So I want to close it at present.