feat: Implement site-specific recipe parsers for ICA and generic fallback

backend/src/quick-import/parsers/base.parser.ts

@@ -0,0 +1,53 @@
+/**
+ * Bas-parser för receptsidor
+ * Alla site-specifika parsers bör extenda denna
+ */
+export interface ParsedRecipe {
+  name: string;
+  description?: string;
+  ingredients: Array<{
+    quantity: number;
+    unit: string;
+    name: string;
+  }>;
+  instructions?: string;
+}
+
+export abstract class RecipeParser {
+  /**
+   * Kontrollera om denna parser kan hantera denna URL
+   */
+  abstract canHandle(url: string): boolean;
+
+  /**
+   * Parsa HTML och extrahera receptdata
+   */
+  abstract parse(html: string): ParsedRecipe;
+
+  /**
+   * Hjälpfunktion: parsa ingrediens-rad
+   */
+  protected parseIngredientLine(line: string): {
+    quantity: number;
+    unit: string;
+    name: string;
+  } | null {
+    const cleaned = line.replace(/<[^>]+>/g, '').trim();
+    if (!cleaned) return null;
+
+    const match = cleaned.match(/^([\d.,]+)?\s*([a-zåäö]*)\s*(.+)$/i);
+    if (!match) {
+      return {
+        quantity: 0,
+        unit: 'st',
+        name: cleaned,
+      };
+    }
+
+    return {
+      quantity: match[1] ? parseFloat(match[1].replace(',', '.')) : 0,
+      unit: (match[2] || 'st').toLowerCase().trim(),
+      name: match[3].trim(),
+    };
+  }
+}