feat: Implement binary_toolchain

[BoleynSu]

See #747

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[alexeagle]

This seems very similar to bazel-contrib/rules_oci#590 by @EdSchouten

I wonder if bazel-lib could provide the abstraction that's needed for this case globally. We should bike-shed on this name because "BinaryInfo" can also apply to a binary run as an action on the exec platform.

[BoleynSu]

Agree we should have the abstraction shared. binary_toolchain is my answer. While there are still some decision we want to make which are not clear to me yet.

I think ideally we only limit the scope of the solution to 2) in bazelbuild/bazel#19645 (comment)

Then we only need to have one toolchain_type for the binary. Using jq as an example.

We will need

toolchain_type(name = "jq_binary_toolchain_type") # User should register different binary to this toolchain
binary_toolchain(name="jq_linux_amd64", binary="@jq_linux_amd64")
toolchain(
    name = "toolchain_linux_amd64",
    toolchain = ":jq_linux_amd64",
    toolchain_type = :jq_binary_toolchain_type",
    target_compatible_with = linux_amd64,
)
resolved_binary(name = "resolved_jq_binary") # This resolves to a binary that run on the target platform

# The jq_toolchain_type will be made private regarding registering, i.e. we only register jq_toolchain to it and do not allow user to register new toolchain to jq_toolchain_type.
toolchain_type(name = "jq_toolchain_type")
jq_toolchain(name = "jq_toolchain") # jq_toolchain use resolved_jq_binary with cfg=exec
toolchain(
    name = "toolchain",
    toolchain = ":jq_toolchain",
    toolchain_type = :jq_toolchain_type",
)