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.

webapp/app.py

@@ -1189,6 +1189,83 @@ def startnet_diff():
     return jsonify({"error": "provide snapshot_id or content"}), 400
 
 
+# ---------------------------------------------------------------------------
+# Routes - Shopfloor boot-menu (data-driven menu.json)
+# ---------------------------------------------------------------------------
+
+SHOPFLOOR_SETUP_DIR = os.path.join(config.ENROLLMENT_SHARE, "shopfloor-setup")
+SHOPFLOOR_MENU_JSON = os.path.join(SHOPFLOOR_SETUP_DIR, "menu.json")
+
+
+def read_shopfloor_menu():
+    """The shopfloor PC-type menu items from menu.json (list; [] if absent)."""
+    try:
+        with open(SHOPFLOOR_MENU_JSON) as fh:
+            return json.load(fh).get("shopfloor", [])
+    except (OSError, json.JSONDecodeError):
+        return []
+
+
+def available_pctypes():
+    """gea-shopfloor-* handler dirs on the share - the only valid menu keys."""
+    try:
+        return sorted(
+            d for d in os.listdir(SHOPFLOOR_SETUP_DIR)
+            if d.startswith("gea-shopfloor-")
+            and os.path.isdir(os.path.join(SHOPFLOOR_SETUP_DIR, d))
+        )
+    except OSError:
+        return []
+
+
+@app.route("/shopfloor-menu", methods=["GET", "POST"])
+def shopfloor_menu():
+    if request.method == "POST":
+        try:
+            items = json.loads(request.form.get("items", "[]"))
+        except json.JSONDecodeError:
+            flash("Invalid menu payload.", "danger")
+            return redirect(url_for("shopfloor_menu"))
+        valid = set(available_pctypes())
+        clean = []
+        for it in items:
+            if not isinstance(it, dict):
+                continue
+            key = (it.get("key") or "").strip()
+            label = (it.get("label") or "").strip()
+            if not key or not label:
+                continue
+            if key not in valid:
+                flash(f"Skipped '{label}': {key} has no shopfloor-setup handler.", "warning")
+                continue
+            clean.append({
+                "key": key,
+                "label": label,
+                "hint": (it.get("hint") or "").strip(),
+                "enabled": bool(it.get("enabled", True)),
+            })
+        if not clean:
+            flash("Refused to save an empty menu.", "danger")
+            return redirect(url_for("shopfloor_menu"))
+        try:
+            os.makedirs(SHOPFLOOR_SETUP_DIR, exist_ok=True)
+            with open(SHOPFLOOR_MENU_JSON, "w") as fh:
+                json.dump({"shopfloor": clean}, fh, indent=2)
+            audit("SHOPFLOOR_MENU_SAVE", f"{len(clean)} items")
+            flash("Shopfloor boot menu saved - WinPE reads it at next boot.", "success")
+        except OSError as exc:
+            flash(f"Could not write menu.json: {exc}", "danger")
+        return redirect(url_for("shopfloor_menu"))
+
+    return render_template(
+        "shopfloor_menu.html",
+        items=read_shopfloor_menu(),
+        available=available_pctypes(),
+        image_types=config.IMAGE_TYPES,
+        friendly_names=config.FRIENDLY_NAMES,
+    )
+
+
 # ---------------------------------------------------------------------------
 # Routes - Audit Log
 # ---------------------------------------------------------------------------