feat: NAPALM drivers for VMware ESXi and vCenter

Two drivers from one package, both in the hypervisor role:

- vmware_esxi talks to one host directly: facts, vmnics and vmkernel
  NICs, CDP/LLDP neighbours, sensors, VMs, datastores and port groups.
- vmware_vcenter talks to a vCenter: every VM of every host it manages,
  with the host as the VM's node, plus distributed port groups. It
  reports no interfaces of its own; the hosts' NICs belong to the hosts.

Both implement the HypervisorDriver VM contract: get_vms, get_vm_config,
start/stop/reboot/suspend_vm and the four snapshot methods, and emit raw
device warnings (maintenance mode, disconnected host, config issues,
host managed by a vCenter, free license making the API read-only).

Every read is a PropertyCollector query for the explicit paths in
paths.py, converted by to_plain() into dicts and lists; the parsers
only ever see that. tools/harvest.py dumps exactly those paths to JSON
and tools/sanitize.py scrubs the dump, so a real host can become a test
fixture without code changes. A VM's vmid is its instance UUID, which
survives vMotion and re-registration; a MoRef does not.

Tested against govmomi's vcsim in ESXi and vCenter mode, including real
power and snapshot tasks. Not yet tested against real hardware.

napalm_vmware/paths.py

@@ -0,0 +1,76 @@
+"""The vSphere property paths the drivers read, per managed object type.
+
+Single source of truth for both the drivers and ``tools/harvest.py``: a
+fixture harvested from a real host contains exactly what the parsers are
+later fed, no more and no less. Adding a path here is the first step of
+adding a field to any getter.
+"""
+
+from __future__ import annotations
+
+HOST = (
+    "name",
+    "summary.hardware",
+    "summary.quickStats",
+    "summary.managementServerIp",
+    "hardware.systemInfo",
+    "runtime.inMaintenanceMode",
+    "runtime.connectionState",
+    "runtime.healthSystemRuntime.systemHealthInfo.numericSensorInfo",
+    "config.product",
+    "config.network.pnic",
+    "config.network.vnic",
+    "config.network.portgroup",
+    "config.network.vswitch",
+    "config.network.dnsConfig",
+    "config.autoStart",
+    "configIssue",
+    "configManager.networkSystem",
+)
+
+VM = (
+    "name",
+    "config.instanceUuid",
+    "config.template",
+    "config.guestId",
+    "config.guestFullName",
+    "config.annotation",
+    "config.firmware",
+    "config.version",
+    "config.hardware.numCPU",
+    "config.hardware.numCoresPerSocket",
+    "config.hardware.memoryMB",
+    "config.hardware.device",
+    "config.bootOptions.bootOrder",
+    "runtime.powerState",
+    "runtime.host",
+    "summary.quickStats",
+    "guest.net",
+    "guest.ipAddress",
+    "guest.toolsStatus",
+    "guest.toolsRunningStatus",
+    "snapshot",
+)
+
+DATASTORE = (
+    "name",
+    "summary",
+)
+
+DV_PORTGROUP = (
+    "name",
+    "config.defaultPortConfig",
+    "config.distributedVirtualSwitch",
+    "config.uplink",
+)
+
+DV_SWITCH = ("name",)
+
+#: Managed object type name -> paths, in the order harvest.py dumps them.
+ALL = {
+    "HostSystem": HOST,
+    "VirtualMachine": VM,
+    "Datastore": DATASTORE,
+    "DistributedVirtualPortgroup": DV_PORTGROUP,
+    "DistributedVirtualSwitch": DV_SWITCH,
+}