[clang-tidy][modernize] Replace memmove/memcpy with std::copy

[kidq330]

Closes #22583

As pointed out in the discussion under the linked issue, the semantics of this check are a little tricky to pin down exactly so this version offers a little less than I'd like and hoping someone with more experience could help.
Other notes:

• Tried my hand at setting up a developer env using a nix flake which was semi-successful, but I wasn't able to add libedit in a way that didn't break compilation, throwing this out here in case someone reading this uses a similar setup and has some pointers
• Also discussed in the linked issue, a similar check can be made to replace memset with std::fill. I'll try to create a tracking issue before this one gets merged, hopefully, and would be willing to work on it as well since they share a lot of aspects.

First contribution so I'd say it will need some post-review fixes

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[kadircet]

can you update clang-tools-extra/clangd/TidyFastChecks.inc in a follow up change, after this check lands in its final shape?

[kidq330]

@kadircet Does the file need further changes from what I've already added?

[kadircet]

@kadircet Does the file need further changes from what I've already added?

probably yes, it'd be great if you can just run https://github.com/llvm/llvm-project/blob/main/clang-tools-extra/clangd/TidyFastChecks.py to generate the edits

[kidq330]

@kadircet I ran the script but it seems that my check was one of the few that did not get updated (see last commit in PR), is this normal?
Here's the cmake command for the build I used:

cmake -G Ninja -S llvm -B static  -DBUILD_SHARED_LIBS=false -DLLVM_ENABLE_PROJECTS="clang;clang-tools-extra" -DCMAKE_BUILD_TYPE="Release" -DLLVM_USE_LINKER=mold -DLLVM_TARGETS_TO_BUILD=X86 -DCMAKE_C_COMPILER="gcc" -DCMAKE_CXX_COMPILER="g++"