shopfloor menu: data-driven from menu.json (picker + webapp editor)

Replace the hardcoded GEA Shopfloor PC-type sub-menu with a data-driven one:
- menu.json on the enrollment share lists the shopfloor items {key=PCTYPE, label, hint, enabled}; key must match a shopfloor-setup/gea-shopfloor-* handler dir.
- select-shopfloor-type.ps1 renders it in WinPE and writes the chosen PCTYPE (mirrors the CMM bay picker); startnet.cmd runs it and falls back to the baked-in menu if the share/picker is unavailable.
- Webapp /shopfloor-menu editor: reorder/rename/hide/add items; the PC-type is a dropdown of existing handler dirs (can't wire a choice to a non-existent type); writes menu.json. Nav link under Tools.
Kills the duplicated-knowledge problem (menu list was hardcoded in startnet AND the handler dirs AND site-config); add a PC-type = drop in the handler dir + it appears in the menu.

playbook/shopfloor-setup/menu.json

@@ -0,0 +1,15 @@
+{
+  "_comment": "Data-driven WinPE shopfloor PC-type menu. Read at boot by select-shopfloor-type.ps1 (mirrors the CMM bay picker) and edited by the PXE webapp. 'key' is the PCTYPE value - it MUST match a shopfloor-setup/gea-shopfloor-<x> handler dir. Order = display order. Set enabled=false to hide without deleting. Deployed to the enrollment share; startnet.cmd falls back to its baked-in menu if this file or the picker is unavailable.",
+  "shopfloor": [
+    { "key": "gea-shopfloor-collections",   "label": "Machine with Collections",    "hint": "eDNC + UDC + Plant Apps",              "enabled": true },
+    { "key": "gea-shopfloor-nocollections", "label": "Machine without Collections", "hint": "eDNC + Plant Apps, no UDC",            "enabled": true },
+    { "key": "gea-shopfloor-common",        "label": "Common",                      "hint": "Timeclock, Lab; WJ Shopfloor only",    "enabled": true },
+    { "key": "gea-shopfloor-keyence",       "label": "Keyence",                     "hint": "VR-3000 / VR-5000 / VR-6000 microscope","enabled": true },
+    { "key": "gea-shopfloor-cmm",           "label": "CMM",                         "hint": "Hexagon PC-DMIS + Protect Viewer",     "enabled": true },
+    { "key": "gea-shopfloor-genspect",      "label": "Genspect",                    "hint": "",                                     "enabled": true },
+    { "key": "gea-shopfloor-heattreat",     "label": "Heattreat",                   "hint": "eDNC + HeatTreat app",                 "enabled": true },
+    { "key": "gea-shopfloor-waxtrace",      "label": "Wax and Trace",               "hint": "",                                     "enabled": true },
+    { "key": "gea-shopfloor-display",       "label": "Display",                     "hint": "kiosk dashboard",                      "enabled": true },
+    { "key": "gea-shopfloor-partmarker",    "label": "Part Marker",                 "hint": "eDNC + Telesis Mark",                  "enabled": true }
+  ]
+}

playbook/shopfloor-setup/select-shopfloor-type.ps1

@@ -0,0 +1,63 @@
+<#
+  select-shopfloor-type.ps1 - data-driven GEA Shopfloor PC-type picker for WinPE.
+
+  Reads the shopfloor menu from menu.json (edited by the PXE webapp), renders a
+  numbered menu, and writes the chosen PCTYPE key (e.g. gea-shopfloor-cmm) to
+  -OutFile. startnet.cmd runs this instead of a hardcoded menu, and falls back
+  to its baked-in menu if this script or menu.json is missing. Mirrors the CMM
+  bay picker (select-cmm-bay.ps1).
+
+  Usage (from startnet.cmd):
+    powershell -NoProfile -ExecutionPolicy Bypass -File select-shopfloor-type.ps1 `
+        -MenuJson Y:\menu.json -OutFile X:\pctype.txt
+  Exit 0 + a written key on success; non-zero (and no file) on any failure so
+  the batch fallback kicks in.
+#>
+param(
+    [Parameter(Mandatory = $true)][string]$MenuJson,
+    [Parameter(Mandatory = $true)][string]$OutFile
+)
+
+$ErrorActionPreference = 'Stop'
+Remove-Item -LiteralPath $OutFile -ErrorAction SilentlyContinue
+
+try {
+    if (-not (Test-Path -LiteralPath $MenuJson)) { Write-Host "menu.json not found: $MenuJson"; exit 2 }
+    $data = Get-Content -LiteralPath $MenuJson -Raw | ConvertFrom-Json
+    $items = @($data.shopfloor | Where-Object { $_.key -and ($_.enabled -ne $false) })
+    if ($items.Count -eq 0) { Write-Host "menu.json has no enabled shopfloor items"; exit 3 }
+
+    while ($true) {
+        Clear-Host
+        Write-Host ""
+        Write-Host "========================================"
+        Write-Host "      GEA Shopfloor PC Sub-Type"
+        Write-Host "========================================"
+        Write-Host ""
+        for ($i = 0; $i -lt $items.Count; $i++) {
+            $n = $i + 1
+            $lbl = $items[$i].label
+            $hint = $items[$i].hint
+            $line = "{0,3}. {1}" -f $n, $lbl
+            if ($hint) { $line = "{0,-45} ({1})" -f $line, $hint }
+            Write-Host $line
+        }
+        Write-Host ""
+        $sel = Read-Host ("Enter your choice (1-{0})" -f $items.Count)
+        $num = 0
+        if ([int]::TryParse($sel, [ref]$num) -and $num -ge 1 -and $num -le $items.Count) {
+            $key = $items[$num - 1].key
+            # OutFile is on X: (WinPE scratch); write the bare PCTYPE key, no BOM/newline surprises
+            [System.IO.File]::WriteAllText($OutFile, $key)
+            Write-Host ""
+            Write-Host ("Selected: {0}  ({1})" -f $items[$num - 1].label, $key)
+            exit 0
+        }
+        Write-Host "Invalid choice - try again."
+        Start-Sleep -Milliseconds 800
+    }
+}
+catch {
+    Write-Host "shopfloor picker error: $($_.Exception.Message)"
+    exit 1
+}