[clang-tools-extra] [clang-query] Load queries and matchers from file during REPL cycle (PR #90603)

[Aaron Ballman via cfe-commits]

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+m functionDecl()
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AaronBallman wrote:

Can you add a few more commands to the file to show that we execute all of the commands rather than just one?

It would also be good to have a test where the file is not found and a test where the file is empty, just to test boundary conditions.

https://github.com/llvm/llvm-project/pull/90603