Add machine-aware maximum product length

app.py

@@ -20,7 +20,10 @@ from flask_httpauth import HTTPBasicAuth
 from werkzeug.security import check_password_hash
 
 from core_presets import CORE_PRESETS
-from machine_constraints import check_production_feasibility
+from machine_constraints import (
+    calculate_machine_max_product_length,
+    check_production_feasibility,
+)
 from conversation_service import (
     ConversationNotFoundError,
     ConversationReportNotFoundError,
@@ -278,6 +281,49 @@ def create_production_feasibility_calculation():
     return jsonify(result), 200
 
 
+@app.route("/api/calculations/machine-max-product-length", methods=["POST"])
+@auth.login_required
+def create_machine_max_product_length_calculation():
+    """Calculate machine-limited product length through the shared domain."""
+    payload = request.get_json(silent=True)
+    allowed = {
+        "machine",
+        "core_diameter_mm",
+        "thickness_mm",
+        "thickness_stddev_mm",
+        "product_width_m",
+        "area_weight_g_m2",
+    }
+    if not isinstance(payload, dict):
+        result = {
+            "status": "invalid_parameter",
+            "invalid": [{"field": "request", "message": "JSON object required"}],
+        }
+    else:
+        unknown = sorted(set(payload) - allowed)
+        if unknown:
+            result = {
+                "status": "invalid_parameter",
+                "invalid": [{
+                    "field": "request",
+                    "message": "unknown request fields: " + ", ".join(unknown),
+                }],
+            }
+        else:
+            result = calculate_machine_max_product_length(
+                machine=payload.get("machine"),
+                core_diameter_mm=payload.get("core_diameter_mm"),
+                thickness_mm=payload.get("thickness_mm"),
+                thickness_stddev_mm=payload.get("thickness_stddev_mm"),
+                product_width_m=payload.get("product_width_m"),
+                area_weight_g_m2=payload.get("area_weight_g_m2"),
+            )
+    log_access(
+        auth.current_user(), "/api/calculations/machine-max-product-length", "POST"
+    )
+    return jsonify(result), 200
+
+
 def _create_pdf(calculation_request):
     result = calculate_roll(calculation_request, build_info=BUILD_INFO)
     report = report_from_calculation_result(result)