refactor: replace integration tests with unit tests using mocked callProvider

Consolidate 24 per-provider integration test files into parameterized
unit tests that mock callProvider, eliminating all production API
dependencies. Tests run instantly with deterministic results.

TypeScript: 131 tests across 10 files (was 27 files)
Python: 86 tests across 7 files (was 12 files)
Made-with: Cursor

Author: homanp

sdk/python/tests/conftest.py

@@ -2,20 +2,12 @@
 pytest configuration and fixtures
 """
 
-import os
-from pathlib import Path
-
 import pytest
-from dotenv import load_dotenv
 
-# Load environment variables from root .env file
-env_path = Path(__file__).parent.parent.parent.parent / ".env"
-load_dotenv(env_path)
+from safety_agent import create_client
 
 
 @pytest.fixture
 def client():
-    """Create a Safety Agent client for testing."""
-    from safety_agent import create_client
-
-    return create_client()
+    """Create a Safety Agent client for testing with a fake API key."""
+    return create_client(api_key="test-key")