Port VM autobackups into pvcworkerd with snaps

Moves VM autobackups from being in-CLI to being handled by the
pvcworkerd system on the primary coordinator. Turns the CLI autobackup
command into an actual API client endpoint rather than having its logic
in the CLI.

In addition, modifies the new autobackup to leverage the new "pvc vm
snapshot" function set, just with special snapshot names. This helps
automate this within the new snapshot scaffolding.

daemon-common/config.py

@@ -406,6 +406,78 @@ def get_configuration():
     return config
 
 
+def get_parsed_autobackup_configuration(config_file):
+    """
+    Load the configuration; this is the same main pvc.conf that the daemons read
+    """
+    print('Loading configuration from file "{}"'.format(config_file))
+
+    with open(config_file, "r") as cfgfh:
+        try:
+            o_config = yaml.load(cfgfh, Loader=yaml.SafeLoader)
+        except Exception as e:
+            print(f"ERROR: Failed to parse configuration file: {e}")
+            os._exit(1)
+
+    config = dict()
+
+    try:
+        o_cluster = o_config["cluster"]
+        config_cluster = {
+            "cluster": o_cluster["name"],
+            "autobackup_enabled": True,
+        }
+        config = {**config, **config_cluster}
+
+        o_autobackup = o_config["autobackup"]
+        if o_autobackup is None:
+            config["autobackup_enabled"] = False
+            return config
+
+        config_autobackup = {
+            "backup_root_path": o_autobackup["backup_root_path"],
+            "backup_root_suffix": o_autobackup["backup_root_suffix"],
+            "backup_tags": o_autobackup["backup_tags"],
+            "backup_schedule": o_autobackup["backup_schedule"],
+        }
+        config = {**config, **config_autobackup}
+
+        o_automount = o_autobackup["auto_mount"]
+        config_automount = {
+            "auto_mount_enabled": o_automount["enabled"],
+        }
+        config = {**config, **config_automount}
+        if config["auto_mount_enabled"]:
+            config["mount_cmds"] = list()
+            for _mount_cmd in o_automount["mount_cmds"]:
+                if "{backup_root_path}" in _mount_cmd:
+                    _mount_cmd = _mount_cmd.format(
+                        backup_root_path=config["backup_root_path"]
+                    )
+                config["mount_cmds"].append(_mount_cmd)
+            config["unmount_cmds"] = list()
+            for _unmount_cmd in o_automount["unmount_cmds"]:
+                if "{backup_root_path}" in _unmount_cmd:
+                    _unmount_cmd = _unmount_cmd.format(
+                        backup_root_path=config["backup_root_path"]
+                    )
+                config["unmount_cmds"].append(_unmount_cmd)
+
+    except Exception as e:
+        raise MalformedConfigurationError(e)
+
+    return config
+
+
+def get_autobackup_configuration():
+    """
+    Get the configuration.
+    """
+    pvc_config_file = get_configuration_path()
+    config = get_parsed_autobackup_configuration(pvc_config_file)
+    return config
+
+
 def validate_directories(config):
     if not os.path.exists(config["dynamic_directory"]):
         os.makedirs(config["dynamic_directory"])