Phase 1 MVP - Complete implementation

- Auth: register, login, JWT with refresh tokens, blocklist
- Projects/Folders/Documents CRUD with soft deletes
- Tags CRUD and assignment
- FTS5 search with highlights and tag filtering
- ADR-001, ADR-002, ADR-003 compliant
- Security fixes applied (JWT_SECRET_KEY, exception handler, cookie secure)
- 25 tests passing

pytest.ini

@@ -0,0 +1,8 @@
+[pytest]
+asyncio_mode = auto
+testpaths = tests
+python_files = test_*.py
+python_functions = test_*
+python_classes = Test*
+filterwarnings =
+    ignore::DeprecationWarning