[clang-tools-extra] [clang-tidy] support query based custom check (PR #131804)

[Congcong Cai via cfe-commits]

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+====================================
+Query Based Custom Clang-Tidy Checks
+====================================
+
+Introduction
+============
+
+This page provides examples of how to add query based custom checks for
+:program:`clang-tidy`.
+
+Custom checks are based on :program:`clang-query` syntax. Every custom checks
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HerrCai0907 wrote:

I will do it in another PR since I do not want to touch clang-query here to make the scope controllable.

https://github.com/llvm/llvm-project/pull/131804