Call fflush for each item in JitDisasmSummary

[EgorBo]

cc @AndyAyersMS who asked for it

[Copilot]

Pull Request Overview

This PR adds an fflush() call to ensure immediate output of JIT disassembly summary messages. The change forces the output buffer to be flushed after each compiled method is logged, providing more reliable debugging output for JIT analysis.

Key changes:

• Added fflush(jitstdout()) after each JIT compilation summary message

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[AndyAyersMS]

FYI, somewhere there's comment that printf(""); does the same thing. Not sure if it's still true though.

[EgorBo]

FYI, somewhere there's comment that printf(""); does the same thing. Not sure if it's still true though.

I actually copied this fflush(jitstdout()) from the JitDisasm routine.