[clang-tools-extra] [IncludeCleaner] display overview (PR #93932)

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TheHillBright wrote:

@kadircet @sam-mccall @kazutakahirata I'm coming back to revive this PR again after 2 years. Rebased on the latest main branch. Now the CI requires your approval again.

Hope this time this can be merged before the upstream changes drastically again...

https://github.com/llvm/llvm-project/pull/93932