[wasm] jiterpreter cleanup and performance improvements (#81707)

[wasm] jiterpreter cleanup and performance improvements (#81707)

* Improves the jiterpreter's code gen performance slightly by removing some redundant work from the compilation hot path and moving it to one-time initialization instead.
* Split the jiterpreter trace generation code into its own file
* Stop using opname.startsWith in trace generation
* Minor logging cleanup
* Remove dead code