SIENTIAPDE-1478

Update pytest_asyncio fixture scopes in conftest.py for improved test isolation and add asyncio_default_fixture_loop_scope in pyproject.toml. Remove outdated scenarios from scenarios.md and delete unused test files for cleaner codebase.

e2e/scenarios.md

@@ -299,25 +299,6 @@ The `pi_web_api_scouter` workflow:
 
 ---
 
-#### Scenario 2.2.2: Zero Affected Rows After Export
-**Description**: PostgreSQL export returns zero affected rows
-
-**Input**:
-- Data that results in `affected_rows: 0` from export
-
-**Expected Behavior**:
-- `export_data_to_postgres` returns `{'affected_rows': 0}`
-- Workflow checks `if data_exported.get('affected_rows', 0) <= 0:` and returns early
-- `write_metrics` NOT called
-- `store_data_package` NOT called
-
-**Assertions**:
-- Early return after export
-- No metrics written
-- Workflow completes without error
-
----
-
 ### 2.3 Error Scenarios
 
 #### Scenario 2.3.1: Redis Connection Error