chore: upgrade to clap v4

[ricochet]

Upstream cargo has upgraded to clap v4.

takes_value has been deprecated. num_args (the replacement for takes_value) will default num_args based on the ArgAction and doesn't need to be set for the verbose flag use-case. But there's one more change. Commands with ArgAction::Count must be u8.

Test caught this:

command=`"/Users/bhayes/repos/bytecodealliance/cargo-component/target/debug/cargo-component" "component" "add"`
code=101
stdout=""
stderr="thread \'main\' panicked at \'assertion failed: `(left == right)`\n  left: `u8`,\n right: `u32`: Argument `verbose`\'s selected action Count contradicts `value_parser` (ValueParser::other(u32))\', /Users/bhayes/.cargo/registry/src/github.com-1ecc6299db9ec823/clap-4.0.12/src/builder/debug_asserts.rs:708:9\nnote: run with `RUST_BACKTRACE=1` environment variable to display a backtrace\n"
', /rustc/a55dd71d5fb0ec5a6a3a9e8c27b2127ba491ce52/library/core/src/ops/function.rs:248:5

---- help stdout ----
thread 'help' panicked at 'Unexpected stdout, failed var.contains(Add a dependency for a WebAssembly component)
├── var:
└── var as str:

command=`"/Users/bhayes/repos/bytecodealliance/cargo-component/target/debug/cargo-component" "component" "help" "add"`
code=101
stdout=""
stderr="thread \'main\' panicked at \'assertion failed: `(left == right)`\n  left: `u8`,\n right: `u32`: Argument `verbose`\'s selected action Count contradicts `value_parser` (ValueParser::other(u32))\', /Users/bhayes/.cargo/registry/src/github.com-1ecc6299db9ec823/clap-4.0.12/src/builder/debug_asserts.rs:708:9\nnote: run with `RUST_BACKTRACE=1` environment variable to display a backtrace\n"
', /rustc/a55dd71d5fb0ec5a6a3a9e8c27b2127ba491ce52/library/core/src/ops/function.rs:248:5

Arg::possible_values has been replaced with Arg::value_parser([...]). Things got a little awkward here. While upstream cargo seems to be able to pass in value_parser = ["1"] (src), we get a downcast error.

stderr="thread \'main\' panicked at \'Mismatch between definition and access of `format_version`. Could not downcast to u32, need to downcast to alloc::string::String\n\', src/commands/metadata.rs:62:25\nnote: run with `RUST_BACKTRACE=1` environment variable to display a backtrace\n"

Kudos on solid test coverage. The tests caught all of these after the build succeeded. I added an additional test around format-version.