[clang] [Doc] Update documentation for no-transitive-change (PR #96453)

[Chuanqi Xu via cfe-commits]

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@@ -652,6 +652,134 @@ in the future. The expected roadmap for Reduced BMIs as of Clang 19.x is:
    comes, the term BMI will refer to the Reduced BMI and the Full BMI will only
    be meaningful to build systems which elect to support two-phase compilation.
 
+Experimental No Transitive Change
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ChuanqiXu9 wrote:

> On "experimental": thanks for clarifying that you meant this as "experimental in the build system". I am afraid that the current wording actually does the opposite and tells that this the compiler support is "experimental" (aka "unstable", aka "don't touch this until it stabilizes").

Yeah, and I like to call it as `experimental with the build system`. Since although the users can only get it from build systems, the core abilities are provided by the compiler. Also when bug reports comes, I believe most of them need to solve in the compiler side. But this doesn't matter though : )

https://github.com/llvm/llvm-project/pull/96453