feat: Add pydantic_settings import check and update requirements

Author: moshesham

check_install.py

@@ -0,0 +1,5 @@
+try:
+    import pydantic_settings
+    print("pydantic_settings is installed")
+except ImportError:
+    print("pydantic_settings is NOT installed")

requirements.txt

@@ -1,6 +1,7 @@
 # Core AI and LLM dependencies
 httpx>=0.25.0
 pydantic>=2.5.0
+pydantic-settings>=2.0.0
 structlog>=23.2.0
 rich>=13.7.0
 click>=8.1.0