feat: Production-ready configurator with Dutch standards, pricing & visual UI

- Update door-models.ts: 7mm VSG 33.1 safety glass, 15mm offset, Taats pivot 60mm
- Add pricing engine (lib/pricing.ts): steel €45/m + glass €140/m² + €650 base
- Wire reactive pricing into Zustand store on every config change
- Fix 3D materials: glass thickness 0.007m, corrected roughness/metalness
- Upgrade scene: apartment environment, wider contact shadows
- Add Dutch height presets: Renovatie 2015mm, Nieuwbouw 2315mm, Plafondhoog 2500mm
- Replace text buttons with visual SVG tiles for door type & grid selection

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

lib/pricing.ts

@@ -0,0 +1,126 @@
+/**
+ * Pricing Engine for Proinn Configurator
+ * Based on Dutch market standard pricing (Metalworks/Aluwdoors reference)
+ */
+
+import {
+  PROFILE_WIDTH,
+  RAIL_HEIGHT_SLIM,
+  RAIL_HEIGHT_ROBUST,
+  type GridLayout,
+  type DoorModel,
+} from './door-models';
+
+// Pricing constants (EUR)
+const STEEL_PRICE_PER_METER = 45;
+const GLASS_PRICE_PER_SQM = 140;
+const BASE_FEE = 650;
+const SIDE_PANEL_SURCHARGE = 250;
+const DOUBLE_DOOR_SURCHARGE = 350;
+const TAATS_MECHANISM_SURCHARGE = 450;
+const HANDLE_PRICES: Record<string, number> = {
+  'beugelgreep': 85,
+  'hoekgreep': 75,
+  'maangreep': 95,
+  'ovaalgreep': 90,
+  'klink': 65,
+  'u-greep': 55,
+  'geen': 0,
+};
+
+function calculateSteelLength(
+  doorWidth: number,
+  doorHeight: number,
+  gridLayout: GridLayout,
+  hasVerticalDivider: boolean
+): number {
+  const innerWidth = doorWidth - PROFILE_WIDTH * 2;
+  let totalLength = doorHeight * 2 + innerWidth * 2;
+
+  if (gridLayout === '3-vlak') {
+    totalLength += innerWidth * 2;
+  } else if (gridLayout === '4-vlak') {
+    totalLength += innerWidth * 3;
+  }
+
+  if (hasVerticalDivider) {
+    totalLength += doorHeight - RAIL_HEIGHT_ROBUST * 2;
+  }
+
+  return totalLength / 1000;
+}
+
+function calculateGlassArea(
+  doorWidth: number,
+  doorHeight: number,
+  gridLayout: GridLayout
+): number {
+  const glassWidth = doorWidth - PROFILE_WIDTH * 2;
+  const glassHeight = doorHeight - RAIL_HEIGHT_ROBUST * 2;
+
+  let dividerArea = 0;
+  if (gridLayout === '3-vlak') {
+    dividerArea = glassWidth * RAIL_HEIGHT_SLIM * 2;
+  } else if (gridLayout === '4-vlak') {
+    dividerArea = glassWidth * RAIL_HEIGHT_SLIM * 3;
+  }
+
+  return (glassWidth * glassHeight - dividerArea) / 1_000_000;
+}
+
+export interface PriceBreakdown {
+  steelCost: number;
+  glassCost: number;
+  baseFee: number;
+  mechanismSurcharge: number;
+  sidePanelSurcharge: number;
+  handleCost: number;
+  totalPrice: number;
+  steelLengthM: number;
+  glassAreaSqm: number;
+}
+
+export function calculatePrice(
+  doorWidth: number,
+  doorHeight: number,
+  doorType: DoorModel,
+  gridLayout: GridLayout,
+  doorConfig: 'enkele' | 'dubbele',
+  sidePanel: 'geen' | 'links' | 'rechts' | 'beide',
+  handle: string
+): PriceBreakdown {
+  const leafCount = doorConfig === 'dubbele' ? 2 : 1;
+  const hasVerticalDivider = doorType === 'paneel';
+
+  const steelLengthPerLeaf = calculateSteelLength(doorWidth, doorHeight, gridLayout, hasVerticalDivider);
+  const glassAreaPerLeaf = calculateGlassArea(doorWidth, doorHeight, gridLayout);
+
+  const totalSteelLength = steelLengthPerLeaf * leafCount;
+  const totalGlassArea = glassAreaPerLeaf * leafCount;
+
+  const sidePanelCount = sidePanel === 'beide' ? 2 : (sidePanel === 'geen' ? 0 : 1);
+
+  const steelCost = Math.round(totalSteelLength * STEEL_PRICE_PER_METER);
+  const glassCost = Math.round(totalGlassArea * GLASS_PRICE_PER_SQM);
+
+  let mechanismSurcharge = 0;
+  if (doorType === 'taats') mechanismSurcharge += TAATS_MECHANISM_SURCHARGE;
+  if (doorConfig === 'dubbele') mechanismSurcharge += DOUBLE_DOOR_SURCHARGE;
+
+  const handleCost = HANDLE_PRICES[handle] || 0;
+  const sidePanelSurchrg = sidePanelCount * SIDE_PANEL_SURCHARGE;
+
+  const totalPrice = steelCost + glassCost + BASE_FEE + mechanismSurcharge + sidePanelSurchrg + handleCost;
+
+  return {
+    steelCost,
+    glassCost,
+    baseFee: BASE_FEE,
+    mechanismSurcharge,
+    sidePanelSurcharge: sidePanelSurchrg,
+    handleCost,
+    totalPrice,
+    steelLengthM: Math.round(totalSteelLength * 100) / 100,
+    glassAreaSqm: Math.round(totalGlassArea * 100) / 100,
+  };
+}