Restore the old InjectPerfOnly behavior where call-site identifiers
are the source line number of the instrumented statement. Also fix
the sync integration test to properly apply the decorator and write
the helper file, and remove dead imports from test_instrumentation.
Replace the old AST-injected codeflash_wrap/InjectPerfOnly sync path
with decorator-based instrumentation matching the async path:
- Add codeflash_performance_sync and codeflash_behavior_sync decorators
with GPU device sync (torch CUDA/MPS, JAX, TensorFlow) via find_spec
- Add sync_devices_before/sync_devices_after with lazy cached detection
- Clean _instrumentation.py to a thin sync/async dispatcher (~47 lines)
- Remove dead code from _instrument_core.py (create_wrapper_function,
create_device_sync_statements, get_call_arguments, etc.)
- Fix all production imports to point at source modules directly
- Drop underscore prefixes on internal helpers (connections, get_async_db,
close_all_connections, detect_device_sync, etc.)
- Rewrite all test files for the new sync path assertions
- Add real-framework GPU device sync tests (torch, jax, tensorflow)
The async behavior decorator now captures stdout per invocation via
io.StringIO into a new `stdout` column in the async_results SQLite
table. The result merger prefers data-sourced stdout over XML stdout,
fixing the root cause of empty stdout in merged async results.
Also fixes: duplicate async parse block in _parse_results.py,
CODEFLASH_RUN_TMPDIR propagation to subprocesses, and removes
dead async code from _stdout_parsers.py and _wrap_decorator.py.
Replace 218-line ASYNC_HELPER_INLINE_CODE string with shutil.copy2 of the
runtime decorator file. Update remaining test files for 10-column SQLite
schema (cpu_runtime). Add cpu_runtime assertions to async E2E tests.
