Manage apikeys in settings

1. More pydantic management of api keys.
2. Clean up of variable declarations from docker compose files, used to block .env imports. Now should be managed ether by settings.py defaults or .env

application/core/settings.py

@@ -2,6 +2,7 @@ import os
 from pathlib import Path
 from typing import Optional
 
+from pydantic import field_validator
 from pydantic_settings import BaseSettings, SettingsConfigDict
 
 current_dir = os.path.dirname(
@@ -158,6 +159,36 @@ class Settings(BaseSettings):
     COMPRESSION_PROMPT_VERSION: str = "v1.0"  # Track prompt iterations
     COMPRESSION_MAX_HISTORY_POINTS: int = 3  # Keep only last N compression points to prevent DB bloat
 
+    @field_validator(
+        "API_KEY",
+        "OPENAI_API_KEY",
+        "ANTHROPIC_API_KEY",
+        "GOOGLE_API_KEY",
+        "GROQ_API_KEY",
+        "HUGGINGFACE_API_KEY",
+        "EMBEDDINGS_KEY",
+        "FALLBACK_LLM_API_KEY",
+        "QDRANT_API_KEY",
+        "ELEVENLABS_API_KEY",
+        "INTERNAL_KEY",
+        mode="before",
+    )
+    @classmethod
+    def normalize_api_key(cls, v: Optional[str]) -> Optional[str]:
+        """
+        Normalize API keys: convert 'None', 'none', empty strings,
+        and whitespace-only strings to actual None.
+        Handles Pydantic loading 'None' from .env as string "None".
+        """
+        if v is None:
+            return None
+        if not isinstance(v, str):
+            return v
+        stripped = v.strip()
+        if stripped == "" or stripped.lower() == "none":
+            return None
+        return stripped
+
 
 # Project root is one level above application/
 path = Path(__file__).parent.parent.parent.absolute()