Initial project setup: NF Hotel Data Analysis API

- Add project structure with domain-driven design organization
- Implement FastAPI endpoints for hotel booking reports
- Add data cleaning, statistics, and LLM report generation services
- Include configuration management and security utilities
- Add repository layer for bookings and metadata access
- Setup testing framework with conftest.py
- Include example files and documentation

.env.example

@@ -0,0 +1,22 @@
+# Copy to .env and fill in real values. Never commit the real .env file.
+
+# Required: clients must send this value in the X-API-Key header.
+API_KEY=change-me-to-a-long-random-secret
+
+# Comma-separated list is not supported by pydantic-settings list parsing via
+# env vars directly; set as a JSON array string if overriding, e.g.:
+# ALLOWED_ORIGINS=["http://localhost:3000"]
+
+# Local dataset fallback used by POST /api/v1/report/from-file
+DEFAULT_DATA_PATH=data/nf_hotel_bookings.csv
+CSV_SEPARATOR=;
+
+# Room types, standard prices and room counts
+METADATA_PATH=data/hotel_metadata.json
+
+# OpenAI-compatible local inference server hosting the analysis LLM
+LLM_BASE_URL=http://localhost:11434/v1
+LLM_API_KEY=not-needed
+LLM_MODEL=qwen3.8-whittle-moe-27b-a17.8b
+# Reasoning models can take several minutes on a full report - keep generous.
+LLM_TIMEOUT_SECONDS=900