feat: improve on api structure, add openapi tags (#2295)

this logically groups api endpoints and gioves them specific openapi tags. which makes them nice on the `/docs` endpoint and makes the `api.py` more approachable
* add wallets list endpoint
* remove trailing slashes from endpoints
* fixup topup url
* fix trailing slash on auth
* backwards compatibility

lnbits/commands.py

@@ -14,7 +14,10 @@ from packaging import version
 
 from lnbits.core.models import Payment, User
 from lnbits.core.services import check_admin_settings
-from lnbits.core.views.api import api_install_extension, api_uninstall_extension
+from lnbits.core.views.extension_api import (
+    api_install_extension,
+    api_uninstall_extension,
+)
 from lnbits.settings import settings
 from lnbits.wallets.base import Wallet