Add set_boot_order tool

Set a VM's BIOS boot device order on an existing VM, e.g.
set_boot_order(name, ['cdrom','disk']) to boot an installer first, or
['disk','cdrom'] post-install. Maps cdrom/disk/ethernet/floppy to the
corresponding Bootable*Device, resolving disk/NIC device keys. Host-aware.

src/mcvsphere/mixins/vm_lifecycle.py

@@ -394,3 +394,71 @@ class VMLifecycleMixin(VSphereMixin):
         conn.wait_for_task(task)
 
         return f"VM renamed from '{name}' to '{new_name}'"
+
+    @mcp_tool(
+        name="set_boot_order",
+        description="Set a VM's BIOS boot device order (e.g. ['cdrom','disk'])",
+        annotations=ToolAnnotations(destructiveHint=True, idempotentHint=True),
+    )
+    def set_boot_order(
+        self, name: str, order: list[str], host: str | None = None
+    ) -> dict[str, Any]:
+        """Set the VM's boot device order.
+
+        Args:
+            name: VM name
+            order: Boot devices in priority order. Each entry is one of:
+                'cdrom' (CD/DVD), 'disk' (hard disk), 'ethernet'/'network' (PXE),
+                or 'floppy'. Devices not listed are tried after those listed.
+            host: Managed ESXi host to target (default: the default host)
+
+        Returns:
+            Dict with the applied boot order
+        """
+        conn = self._conn(host)
+        vm = conn.find_vm(name)
+        if not vm:
+            raise ValueError(f"VM '{name}' not found")
+
+        disk_key = next(
+            (d.key for d in vm.config.hardware.device
+             if isinstance(d, vim.vm.device.VirtualDisk)),
+            None,
+        )
+        nic_key = next(
+            (d.key for d in vm.config.hardware.device
+             if isinstance(d, vim.vm.device.VirtualEthernetCard)),
+            None,
+        )
+
+        boot_devices = []
+        for item in order:
+            kind = item.strip().lower()
+            if kind in ("cdrom", "cd", "dvd"):
+                boot_devices.append(vim.vm.BootOptions.BootableCdromDevice())
+            elif kind in ("disk", "hdd", "hd"):
+                if disk_key is None:
+                    raise ValueError("VM has no virtual disk to boot from")
+                boot_devices.append(
+                    vim.vm.BootOptions.BootableDiskDevice(deviceKey=disk_key)
+                )
+            elif kind in ("ethernet", "nic", "network", "pxe"):
+                if nic_key is None:
+                    raise ValueError("VM has no network adapter to boot from")
+                boot_devices.append(
+                    vim.vm.BootOptions.BootableEthernetDevice(deviceKey=nic_key)
+                )
+            elif kind in ("floppy", "fd"):
+                boot_devices.append(vim.vm.BootOptions.BootableFloppyDevice())
+            else:
+                raise ValueError(
+                    f"Unknown boot device '{item}'. Use cdrom/disk/ethernet/floppy."
+                )
+
+        config_spec = vim.vm.ConfigSpec(
+            bootOptions=vim.vm.BootOptions(bootOrder=boot_devices)
+        )
+        task = vm.ReconfigVM_Task(spec=config_spec)
+        conn.wait_for_task(task)
+
+        return {"vm": name, "boot_order": [d.strip().lower() for d in order]}