Use Profile-Guided Optimization (PGO) for the compiler itself

Hi!

Since the compiler is to be rewritten in Go, I suggest considering using the Profile-Guided Optimization (PGO) option to optimize the Typescript compiler itself. Go [supports](https://go.dev/doc/pgo) PGO since 1.20 so it's an available option for the project. PGO for compiler-like workloads works especially well - e.g. check my PGO [benchmarks](https://github.com/zamazan4ik/awesome-pgo?tab=readme-ov-file#compilers-and-interpreters) for compilers (even if most of are for non-Go projects, the results should be pretty the same for Go since it uses the same ideas).

I suggest you the following plan:

* Perform PGO benchmarks for the compiler. It will require thinking about the training workload - I think compiling any Typescript project would be a good option for most of the use-cases
* Providing some scripts for simplifying building the compiler with PGO
* Integrating PGO optimization step into the CI pipeline so end-users will get a PGO-optimized version of the compiler.

I understand that the project is in its early-stages and probably there are more important things to finish at the moment. If this is true, just consider the issue as a point of improvement for the future versions. I believe that improving the compiler performance is a valuable-enough things for the end-users.

Thank you.

P.S. If you think that Discussions is a better place for such issues - feel free to move it there.

Start by reviewing the Go 1.20 PGO documentation and the compiler's current build and CI entry points. Establish a representative TypeScript training workload, benchmark PGO against the baseline, and assess whether CI integration produces a measurable benefit. The issue names no specific files or tests.

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