inventory: report device class (form factor)

Derive a coarse device_class from SMBIOS chassis type + PCSystemType, with
VM detection (manufacturer/model) and Windows Server OS taking precedence:
Laptop / Desktop / Server / Tablet / Virtual Machine / Unknown. Surfaced in
opsbase on the device list and Hardware tab.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/inventory.rs

@@ -154,10 +154,42 @@ $installed_software = @($installed_software | Sort-Object name, version)
 
 $os_release = "$($os.Version)"
 if ($displayVersion) { $os_release = "$($os.Version) $displayVersion" }
+
+# Device class — a coarse form factor for asset grouping. VM first (most
+# specific), then Windows Server OS, then the SMBIOS chassis type, then the
+# computer-system PCSystemType as a fallback.
+$enc = Get-CimInstance -ClassName Win32_SystemEnclosure -ErrorAction SilentlyContinue | Select-Object -First 1
+$chassis = @(); if ($enc) { $chassis = @($enc.ChassisTypes) }
+$man = "$($cs.Manufacturer)".ToLower()
+$mod = "$($cs.Model)".ToLower()
+$device_class = 'Unknown'
+if ($man -match 'vmware|virtualbox|innotek|qemu|xen|parallels|kvm' -or $mod -match 'virtual machine|vmware|virtualbox|kvm|qemu') {
+    $device_class = 'Virtual Machine'
+} elseif ("$($os.Caption)" -match 'Server') {
+    $device_class = 'Server'
+} else {
+    foreach ($ct in $chassis) {
+        if ($ct -in 8,9,10,14) { $device_class = 'Laptop'; break }
+        elseif ($ct -in 30,31,32) { $device_class = 'Tablet'; break }
+        elseif ($ct -in 17,23,28,29) { $device_class = 'Server'; break }
+        elseif ($ct -in 3,4,5,6,7,13,15,16,24) { $device_class = 'Desktop'; break }
+    }
+    if ($device_class -eq 'Unknown') {
+        switch ([int]$cs.PCSystemType) {
+            1 { $device_class = 'Desktop' }
+            2 { $device_class = 'Laptop' }
+            3 { $device_class = 'Desktop' }
+            4 { $device_class = 'Server' }
+            5 { $device_class = 'Server' }
+        }
+    }
+}
+
 $result = [pscustomobject]@{
     serial_number          = $bios.SerialNumber
     manufacturer           = $cs.Manufacturer
     model                  = $cs.Model
+    device_class           = $device_class
     domain                 = $cs.Domain
     os_distro              = $os.Caption
     os_release             = $os_release