Add lint to suggest as_chunks over chunks_exact with constant

[rommeld]

Adds a new lint chunks_exact_to_as_chunks that suggests using as_chunks instead of chunks_exact when the chunk size is a compile-time constant.

changelog: [chunks_exact_to_as_chunks]: Suggest using slice.as_chunks::<N>() when chunks_exact(N) is called with a compile-time constant. This provides better ergonomics and type safety.

fixes rust-lang/rust-clippy#15882

[rustbot]

r? @Jarcho

rustbot has assigned @Jarcho. They will have a look at your PR within the next two weeks and either review your PR or reassign to another reviewer.

Use r? to explicitly pick a reviewer

[rustbot]

:warning: Warning :warning:

• There are issue links (such as #123) in the commit messages of the following commits. Please move them to the PR description, to avoid spamming the issues with references to the commit, and so this bot can automatically canonicalize them to avoid issues with subtree.
  • 210a439be81b6caea318985099a57ac6a028f640

[github-actions[bot]]

Lintcheck changes for 219eca31fb19ef3e0f718b303b5074ad45413019

Lint	Added	Removed	Changed
clippy::chunks_exact_with_const_size	9	0	0

This comment will be updated if you push new changes

[rustbot]

This PR was rebased onto a different master commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

[rustbot]

:warning: Warning :warning:

• There are issue links (such as #123) in the commit messages of the following commits. Please move them to the PR description, to avoid spamming the issues with references to the commit, and so this bot can automatically canonicalize them to avoid issues with subtree.
  • 3d3d2bef1058f547623cf7894b9ec11dc2f9b129

[Jarcho]

FCP started: https://rust-lang.zulipchat.com/#narrow/channel/257328-clippy/topic/FCP.3A.20.60chunks_exact_with_const_size.60/with/556737670

[rustbot]

Reminder, once the PR becomes ready for a review, use @rustbot ready.