Allow to start wallet API by cashu --daemon (#243)

* Allow to start wallet API by cashu --daemon

* Provide access to wallet name via settings

* Make format

* Use flag is_eager for daemon option

* add setting api_host

---------

Co-authored-by: callebtc <93376500+callebtc@users.noreply.github.com>

cashu/wallet/api/api_server.py

@@ -0,0 +1,13 @@
+import uvicorn
+
+from ...core.settings import settings
+
+
+def start_api_server(port=settings.api_port, host=settings.api_host):
+    config = uvicorn.Config(
+        "cashu.wallet.api.app:app",
+        port=port,
+        host=host,
+    )
+    server = uvicorn.Server(config)
+    server.run()