fix: Fix all failing test files with proper mocking and imports

- test_tiered_context.py: Fix aggregate imports to src.aggregate
- test_gemini_cli_adapter_parity.py: Fix subprocess.Popen mock path and JSON format
- test_gemini_cli_edge_cases.py: Fix mock path, JSON format, and adapter initialization
- test_gemini_cli_parity_regression.py: Fix mock path, reset global adapter
- test_token_usage.py: Fix SimpleNamespace mock structure for gemini response

config.toml

@@ -15,7 +15,7 @@ paths = [
     "C:\\projects\\manual_slop\\tests\\artifacts\\temp_livetoolssim.toml",
     "C:\\projects\\manual_slop\\tests\\artifacts\\temp_liveexecutionsim.toml",
 ]
-active = "C:\\projects\\manual_slop\\tests\\artifacts\\temp_project.toml"
+active = "C:\\projects\\manual_slop\\tests\\artifacts\\temp_livetoolssim.toml"
 
 [gui.show_windows]
 "Context Hub" = true