gh-149564: Propagate call-site hotness to callees via dynamic exits

[anujbharambe]

Summary

• When a hot loop calls many distinct exec()-generated functions, the loop trace fires _DYNAMIC_EXIT on each call because the function version guard fails for each different callee. Each callee's RESUME_CHECK_JIT counter starts high and only decrements by 1 per call, so with ~60 calls per callee, the counter never reaches zero and the callee never gets its own executor.
• This PR fixes the issue by boosting the callee's RESUME counter to trigger immediately when _DYNAMIC_EXIT or _COLD_DYNAMIC_EXIT lands on a RESUME_CHECK_JIT instruction.
  Being called from a hot trace via dynamic exit is strong evidence the callee deserves compilation.

Changes

• Python/bytecodes.c: Added counter boost logic to _DYNAMIC_EXIT and _COLD_DYNAMIC_EXIT
• Python/executor_cases.c.h: Regenerated
• Lib/test/test_capi/test_opt.py: Added test_dynamic_exit_boosts_resume

Risks

• Memory: Compiling many small callees increases memory usage. Acceptable since the backoff mechanism prevents runaway recompilation on failure.
• Overhead: The if (target->op.code == RESUME_CHECK_JIT) check is a single byte comparison on the dynamic exit path (already cold/rare). Negligible cost.

AI Disclosure: Some parts of the code and this PR were written with the help of Claude(AI).

• Issue: JIT doesn't trace exec()-generated functions called from hot loops #149564

[picnixz]

I'm not very familiary with this part of the code, but I don't like having an LLM touch the bytecode properly. In addition, I don't think dynamic exits are really common apart from specific use cases, and we need to see how it affects regular code (we are still adding checks). So I would suggest that we first discuss whether the feature is acceptable before creating a PR, especially with LLM. This is valid for any issues: don't create PRs unless we reached a consensus.

[picnixz]

How can it "boost" its counter? This sets its counter to 0 here. So it resets it. Not boost it.

[bedevere-app]

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