Docs: Consolidate admin documentation and migrate reference data

- Created LOCAL_DEVELOPMENT_GUIDE.md and DEPLOYMENT_GUIDE_MANUAL.md from legacy txt files.
- Migrated country/time_zone data and requirements.txt to documentation/reference_data/.
- Removed redundant admin/documentation/ and admin/data_files/ directories.
- Enhanced app/lib_schema_v3.py to explicitly capture 'required' fields from DB 'NOT NULL' constraint.
- Added verification tests for schema logic and standalone DB connectivity.

tests/conftest_mock.py

@@ -0,0 +1,10 @@
+import sys
+from unittest.mock import MagicMock
+
+# Create a mock for app.config before any other app imports
+mock_config = MagicMock()
+mock_config.settings = MagicMock()
+
+# Manually inject into sys.modules
+sys.modules["app.config"] = mock_config
+print("MOCKED: app.config")