Add settings configuration using Pydantic

settings.py

@@ -0,0 +1,12 @@
+from __future__ import annotations
+from pydantic import BaseModel
+
+
+class Settings(BaseModel):
+    clip_model_id: str = "openai/clip-vit-base-patch32"
+    max_image_mb: int = 8
+    default_domain_top_n: int = 2
+    default_top_k: int = 5
+
+
+settings = Settings()