Add C API to notify when tracing/profiling is enabled or disabled

Feature or enhancement

Proposal:

There is currently no way to be notified when tracing/profiling is enabled or disabled. This forces tools that want different behavior based on tracing/profiling enablement (e.g., JIT compilers) to poll on every function call, adding significant overhead.
PEP-523 established frame evaluation hooks as an officially supported extension point for JITs. However, JITs using this API have no efficient way to know when tracing/profiling is enabled and fall back to the interpreter.
I propose adding a small C API enhancement allowing callbacks to be registered when trace/profile functions are set or cleared.

Has this already been discussed elsewhere?

No response given

Links to previous discussion of this feature:

No response

Linked PRs

• gh-144691

檢視 PEP-523、frame evaluation hooks，以及現有的 trace/profile 函式設定與清除路徑；該 issue 未指定特定檔案或測試。當 C API 讓工具能夠註冊 tracing/profiling 啟用狀態變更的 callback，而不必進行 polling，且行為與連結的 PR gh-144691 一致時，工作即告完成。