feat: D&D SRD 5.2 API — FastAPI app with flat JSON caching

- Data fetched from Open5e API: 3,215 items (339 spells, 330 creatures,
  24 classes, 2,319 magic items, 203 equipment)
- FastAPI app with API key auth (X-API-Key header or ?api_key= param)
- Sliding window rate limiting (60 req/min, 10K req/day)
- Dice rolling endpoint (e.g., /api/dice/roll?spec=2d20+5)
- Full-text search across all resource types
- Pagination, filtering (name, level, school, class, etc.)
- Admin CLI for API key management
- nginx + systemd service ready for deployment

README.md

@@ -0,0 +1,59 @@
+# D&D SRD 5.2 API
+
+An open REST API for the Dungeons & Dragons 5.2 System Reference Document (SRD), served at **[dnd.jezzahehn.com](https://dnd.jezzahehn.com)**.
+
+Powered by [Open5e](https://api.open5e.com) data with flat JSON caching.
+
+## Endpoints
+
+| Endpoint | Description |
+|----------|-------------|
+| `GET /api` | API root — list all available resources |
+| `GET /api/spells` | List spells (filter by name, level, school, class, etc.) |
+| `GET /api/spells/{key}` | Get a specific spell |
+| `GET /api/creatures` | List creatures/monsters |
+| `GET /api/creatures/{key}` | Get a specific creature |
+| `GET /api/classes` | List classes |
+| `GET /api/classes/{key}` | Get a specific class |
+| `GET /api/magic-items` | List magic items |
+| `GET /api/magic-items/{key}` | Get a specific magic item |
+| `GET /api/equipment` | List equipment |
+| `GET /api/equipment/{key}` | Get specific equipment |
+| `GET /api/dice/roll` | Roll dice (`?spec=2d20+5`) |
+| `GET /api/search` | Search across all resources (`?q=fireball`) |
+| `GET /api/docs` | Interactive API documentation (Swagger UI) |
+
+## Authentication
+
+Pass your API key via `X-API-Key` header or `?api_key=` query parameter.
+
+```bash
+curl -H "X-API-Key: your-key-here" https://dnd.jezzahehn.com/api/spells
+```
+
+## Running Locally
+
+```bash
+pip install -r requirements.txt
+python scripts/fetch_data.py
+uvicorn app.main:app --reload
+```
+
+## Managing API Keys
+
+```bash
+python scripts/manage_keys.py list          # List all keys
+python scripts/manage_keys.py create "name"  # Create a new key
+python scripts/manage_keys.py revoke <key>   # Revoke a key
+```
+
+## Data
+
+- **Spells:** 339
+- **Creatures:** 330
+- **Classes:** 24
+- **Magic Items:** 2,319
+- **Equipment:** 203
+- **Total:** 3,215 items
+
+Data is fetched from [Open5e](https://api.open5e.com) and cached as flat JSON files in `data/`.