[compiler] Add support for diagnostic hints (#34126)

Hints are meant as additional information to present to the developer
about an error. The first use-case here is for the suggestion to name
refs with "-Ref" if we encounter a mutation that looks like it might be
a ref. The original error printing used a second error detail which
printed the source code twice, a hint with just extra text is less
noisy.

DiffTrain build for [6ffcac8558efbd204c7df5d52787a90e507dd8d7](https://github.com/facebook/react/commit/6ffcac8558efbd204c7df5d52787a90e507dd8d7)