api: don't execute callbacks within a greenlet if we're already in one

Prevents infinite recursion when the loacl context is lost when switching
between greenlets.

pyinfra/api/command.py

@@ -8,7 +8,7 @@
 import gevent
 from typing_extensions import Unpack
 
-from pyinfra.context import ctx_config, ctx_host
+from pyinfra.context import LocalContextObject, ctx_config, ctx_host
 
 from .arguments import ConnectorArguments
 
@@ -225,6 +225,12 @@ def execute(self, state: "State", host: "Host", connector_arguments: ConnectorAr
         if "state" in argspec.args and "host" in argspec.args:
             return self.function(state, host, *self.args, **self.kwargs)
 
+        # If we're already running inside a greenlet (ie a nested callback) just execute the func
+        # without any gevent.spawn which will break the local host object.
+        if isinstance(host, LocalContextObject):
+            self.function(*self.args, **self.kwargs)
+            return
+
         def execute_function():
             with ctx_config.use(state.config.copy()):
                 with ctx_host.use(host):