refactor: remove Ollama integration and unused AI configuration

- Remove src/models/ollama_client.py, embeddings.py, embeddings_ollama.py
- Remove model aliases and AI config from settings (both config.py files)
- Update health endpoints to only check database connectivity
- Update tests to reflect database-only health checks
- Update README, .env.example, and OIDC docstrings

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/shared/config.py

@@ -52,31 +52,6 @@ class Settings(BaseSettings):
     # Logging
     log_level: str = "DEBUG"
 
-    # Ollama Configuration (for AI orchestration)
-    ollama_base_url: str  # Required - set OLLAMA_BASE_URL in .env
-    ollama_timeout: int = 300  # 5 minutes
-
-    # Model Configuration
-    default_model: str = "mistral-nemo-large:latest"
-    agent_model: str = "mistral-nemo-large:latest"
-    code_models: str = "mistral-nemo-large:latest"
-
-    # System Prompt Variant (for A/B testing)
-    system_prompt_variant: str = "v8_holistic"
-
-    # Agent Configuration
-    agent_fallback_enabled: bool = True
-
-    # Model Aliases (OpenAI → Local)
-    alias_gpt35: str = "gemma:7b"
-    alias_gpt4: str = "mistral:7b"
-    alias_gpt4_turbo: str = "mixtral:8x7b"
-    alias_gpt4_code: str = "codestral:latest"
-
-    # Memory Configuration
-    memory_tier1_max_turns: int = 10
-    memory_consolidation_threshold: int = 10
-
     # Qdrant Configuration
     qdrant_host: str = "qdrant"
     qdrant_port: int = 6333
@@ -84,11 +59,6 @@ class Settings(BaseSettings):
     qdrant_collection_documents: str = "core_api_documents"
     qdrant_collection_user_facts: str = "core_api_user_facts"
 
-    # Embeddings (using Ollama)
-    embedding_model: str = "nomic-embed-text"
-    embedding_dimension: int = 768
-    embedding_batch_size: int = 32
-
     # Search Configuration
     search_provider: str = "searxng"
     searxng_url: str  # Required - set SEARXNG_URL in .env
@@ -128,20 +98,6 @@ class Settings(BaseSettings):
     authentik_username: str = ""
     authentik_password: str = ""
 
-    @property
-    def model_aliases(self) -> dict:
-        """Computed property for model aliases"""
-        return {
-            "gpt-3.5-turbo": self.alias_gpt35,
-            "gpt-4": self.alias_gpt4,
-            "gpt-4-turbo": self.alias_gpt4_turbo,
-            "gpt-4-code": self.alias_gpt4_code,
-        }
-
-    def get_code_models(self) -> list[str]:
-        """Parse comma-separated code models"""
-        return [m.strip().strip('"').strip("'") for m in self.code_models.split(",") if m.strip()]
-
     class Config:
         env_file = ".env"
         case_sensitive = False