feat(agentic-rag): add multi-provider LLM, auth, and Docker support

## Added
- Multi-provider LLM support with factory pattern (8 providers):
  * OpenAI, Z.AI, OpenCode Zen, OpenRouter, Anthropic, Google, Mistral, Azure
- Authentication system: JWT + API Key dual-mode
- Provider management API (/api/v1/providers)
- Docker containerization (Dockerfile + docker-compose.yml)
- Updated documentation in main.py

## Modified
- Documents API: added authentication
- Query API: support for provider/model selection
- RAG service: dynamic LLM provider selection
- Config: multi-provider settings

## Infrastructure
- Qdrant vector store integration
- Redis support (optional)
- Health check endpoints

🚀 Ready for production deployment

requirements.txt

@@ -0,0 +1,52 @@
+# AgenticRAG Requirements
+# Core dependencies
+
+# FastAPI and web framework
+fastapi>=0.104.0
+uvicorn[standard]>=0.24.0
+python-multipart>=0.0.6
+python-jose[cryptography]>=3.3.0
+passlib[bcrypt]>=1.7.4
+
+# Datapizza AI framework
+datapizza-ai>=0.1.0
+datapizza-ai-core>=0.1.0
+
+# LLM Clients
+datapizza-ai-clients-openai>=0.0.12
+# Additional providers will be installed via pip in Dockerfile
+
+# Embeddings
+datapizza-ai-embedders-openai>=0.0.6
+
+# Vector Store
+datapizza-ai-vectorstores-qdrant>=0.0.9
+qdrant-client>=1.7.0
+
+# Document Processing
+datapizza-ai-modules-parsers-docling>=0.0.1
+
+# Tools
+datapizza-ai-tools-duckduckgo>=0.0.1
+
+# Configuration and utilities
+pydantic>=2.5.0
+pydantic-settings>=2.1.0
+python-dotenv>=1.0.0
+httpx>=0.25.0
+aiofiles>=23.2.0
+
+# Observability
+opentelemetry-api>=1.21.0
+opentelemetry-sdk>=1.21.0
+opentelemetry-instrumentation-fastapi>=0.42b0
+
+# Testing
+pytest>=7.4.0
+pytest-asyncio>=0.21.0
+httpx>=0.25.0
+
+# Development
+black>=23.0.0
+ruff>=0.1.0
+mypy>=1.7.0