Copy curses frontend sources and canonical curses, DBM, Tcl and DTrace
integration tests from CPython v3.15.0 through update_lib. Preserve
upstream optional-native/resource/configuration gates and canonical file
modes, without adding native implementations or custom skips.
Validate source identity, hooks and default/frozen compile-only checks.
Native runtime integration and probe execution remain unvalidated.
Assisted-by: OpenAI Codex: model version unavailable
