feat(back-end front-end): integration with twint

frontend/src/app/features/calculator/calculator-page.component.ts

@@ -49,7 +49,11 @@ export class CalculatorPageComponent implements OnInit {
     this.route.queryParams.subscribe(params => {
         const sessionId = params['session'];
         if (sessionId) {
-            this.loadSession(sessionId);
+            // Avoid reloading if we just calculated this session
+            const currentRes = this.result();
+            if (!currentRes || currentRes.sessionId !== sessionId) {
+                this.loadSession(sessionId);
+            }
         }
     });
   }

frontend/src/app/features/calculator/services/quote-estimator.service.ts

@@ -215,7 +215,7 @@ export class QuoteEstimatorService {
                      
                      const settings = {
                          complexityMode: request.mode.toUpperCase(),
-                         material: this.mapMaterial(request.material),
+                         material: request.material,
                          quality: request.quality,
                          supportsEnabled: request.supportEnabled,
                          color: item.color || '#FFFFFF',
@@ -317,14 +317,6 @@ export class QuoteEstimatorService {
     });
   }
 
-  private mapMaterial(mat: string): string {
-    const m = mat.toUpperCase();
-    if (m.includes('PLA')) return 'pla_basic';
-    if (m.includes('PETG')) return 'petg_basic';
-    if (m.includes('TPU')) return 'tpu_95a';
-    return 'pla_basic';
-  }
-
   // Consultation Data Transfer
   private pendingConsultation = signal<{files: File[], message: string} | null>(null);