docs: add coding agent section to README and docs index

README.md

@@ -157,6 +157,17 @@ sunbeam check                   # Run all functional probes
 sunbeam check devtools          # Scoped to namespace
 ```
 
+### Coding Agent
+
+```bash
+sunbeam code                    # Terminal coding agent (connects to Sol via gRPC)
+sunbeam code start --model devstral-small  # Override model
+sunbeam code demo               # Demo TUI without Sol connection
+sunbeam reindex-code --org studio          # Index repos into Sol's code search
+```
+
+See [docs/sol-code.md](docs/sol-code.md) for full documentation.
+
 ### Passthrough
 
 ```bash