[clang-tools-extra] [clang-doc][cmake] Copy assets to build directory (PR #95187)

[Paul Kirth via cfe-commits]

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@@ -25,3 +25,11 @@ install(FILES ../assets/clang-doc-default-stylesheet.css
 install(FILES ../assets/index.js
   DESTINATION "${CMAKE_INSTALL_DATADIR}/clang"
   COMPONENT clang-doc)
+
+add_custom_target(copy-clang-doc-assets
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ilovepi wrote:

I think this is addressed now. I more or less cribed directly from the clang header example. Initially I tried to have the function be a bit more generic and put it in `llvm/cmake/modules/CopyLLVMFiles.cmake`, but my normal methods of including don't seem to work in `clang-doc`. Likely I'm just holding that part wrong, but I don't see anything in `clang-tools-extra` using `include(AddLLVM)` or some other module. 

Happy to refactor if you have some other suggestions.

https://github.com/llvm/llvm-project/pull/95187