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/parse/lldp.py

@@ -0,0 +1,33 @@
+"""NAPALM ``get_lldp_neighbors`` from ``HostNetworkSystem.QueryNetworkHint``.
+
+ESXi listens for CDP on standard vSwitches by default and for LLDP where a
+vDS enables it. Both answers come back per vmnic in one hint; LLDP is
+preferred because it names the switch port the way the switch itself does.
+"""
+
+from __future__ import annotations
+
+from typing import Any
+
+
+def _lldp(info: dict[str, Any]) -> dict[str, str] | None:
+    if not info.get("portId"):
+        return None
+    params = {p.get("key"): p.get("value") for p in info.get("parameter", [])}
+    hostname = params.get("System Name") or info.get("chassisId", "")
+    return {"hostname": str(hostname), "port": str(info["portId"])}
+
+
+def _cdp(info: dict[str, Any]) -> dict[str, str] | None:
+    if not info.get("portId"):
+        return None
+    return {"hostname": str(info.get("devId", "")), "port": str(info["portId"])}
+
+
+def lldp_neighbors(hints: list[dict[str, Any]]) -> dict[str, list[dict[str, str]]]:
+    result: dict[str, list[dict[str, str]]] = {}
+    for hint in hints:
+        neighbor = _lldp(hint.get("lldpInfo") or {}) or _cdp(hint.get("connectedSwitchPort") or {})
+        if neighbor:
+            result[hint["device"]] = [neighbor]
+    return result