vms: init graceful shutdown for GUI

- add python modules for qemu protocols: QMP (hardware interactions) and QGA (guest service interaction)
- refactor state directory: remove name from path (already contains url)
- add impure vm test for basic qmp interaction
- simplify existing vm persistance test (factor out shared code)
- integrate graceful shutdown into GUI

the GUI integration still needs to be improved later:
- add fallback in case system doesn't react to powerdown button
- shutdown GUI switch fails if VM hasn't been started yet, and then remains in a wrong position

pkgs/clan-cli/clan_cli/machines/machines.py

@@ -1,6 +1,11 @@
 import json
 import logging
+from os import path
 from pathlib import Path
+from time import sleep
+
+from clan_cli.dirs import vm_state_dir
+from qemu.qmp import QEMUMonitorProtocol
 
 from ..cmd import run
 from ..errors import ClanError
@@ -30,6 +35,14 @@ class Machine:
         self.build_cache: dict[str, Path] = {}
 
         self._deployment_info: None | dict[str, str] = deployment_info
+        state_dir = vm_state_dir(flake_url=str(self.flake), vm_name=self.name)
+
+        self.qmp_socket: Path = state_dir / "qmp.sock"
+        self.qga_socket: Path = state_dir / "qga.sock"
+
+        print(f"qmp_socket: {self.qmp_socket}")
+        self._qmp = QEMUMonitorProtocol(path.realpath(self.qmp_socket))
+        self._qmp_connected = False
 
     def __str__(self) -> str:
         return f"Machine(name={self.name}, flake={self.flake})"
@@ -46,6 +59,28 @@ class Machine:
         )
         return self._deployment_info
 
+    def qmp_connect(self) -> None:
+        if not self._qmp_connected:
+            tries = 100
+            for num in range(tries):
+                try:
+                    # the socket file link might be outdated, therefore re-init the qmp object
+                    self._qmp = QEMUMonitorProtocol(path.realpath(self.qmp_socket))
+                    self._qmp.connect()
+                    self._qmp_connected = True
+                    log.debug("QMP Connected")
+                    return
+                except FileNotFoundError:
+                    if num < 99:
+                        sleep(0.1)
+                        continue
+                    else:
+                        raise
+
+    def qmp_command(self, command: str) -> dict:
+        self.qmp_connect()
+        return self._qmp.command(command)
+
     @property
     def target_host_address(self) -> str:
         # deploymentAddress is deprecated.