v0.1.0 — Phase 1: Go Backend + SQLite + Seed Data

- Wails project setup (Go + React-TS)
- SQLite schema (allergens, additives, products, week_plans, plan_entries, special_days)
- 14 EU allergens (LMIV 1169/2011)
- 24 German food additives
- 99 products imported from Excel with allergen/additive mappings
- Full Wails bindings (CRUD for products, week plans, entries, special days)
- OTA updater stub (version check against HTTPS endpoint)
- Pure Go SQLite (no CGO) for easy Windows cross-compilation

frontend/src/components/AllergenPicker.tsx

@@ -0,0 +1,106 @@
+import { Allergen } from '../types';
+
+interface AllergenPickerProps {
+  allergens: Allergen[];
+  selectedIds: string[];
+  onChange: (selectedIds: string[]) => void;
+  className?: string;
+}
+
+// Deutsche Namen für Allergene (nach EU-Verordnung)
+const ALLERGEN_NAMES: Record<string, string> = {
+  'a': 'Glutenhaltige Getreide',
+  'b': 'Krebstiere',
+  'c': 'Eier', 
+  'd': 'Fisch',
+  'e': 'Erdnüsse',
+  'f': 'Soja',
+  'g': 'Milch/Laktose',
+  'h': 'Schalenfrüchte',
+  'i': 'Sellerie',
+  'j': 'Senf',
+  'k': 'Sesam',
+  'l': 'Schwefeldioxid',
+  'm': 'Lupinen', 
+  'n': 'Weichtiere'
+};
+
+export function AllergenPicker({ allergens, selectedIds, onChange, className = '' }: AllergenPickerProps) {
+  const handleToggle = (allergenId: string) => {
+    if (selectedIds.includes(allergenId)) {
+      onChange(selectedIds.filter(id => id !== allergenId));
+    } else {
+      onChange([...selectedIds, allergenId]);
+    }
+  };
+
+  // Sortierte Allergene (a-n)
+  const sortedAllergens = [...allergens].sort((a, b) => a.id.localeCompare(b.id));
+
+  return (
+    <fieldset className={`border border-gray-300 rounded-md p-4 ${className}`}>
+      <legend className="text-sm font-medium text-gray-900 px-2">
+        Allergene auswählen
+      </legend>
+      
+      <div 
+        className="grid grid-cols-2 gap-3 mt-3"
+        role="group"
+        aria-labelledby="allergen-picker-legend"
+      >
+        {sortedAllergens.map(allergen => {
+          const isSelected = selectedIds.includes(allergen.id);
+          const displayName = ALLERGEN_NAMES[allergen.id] || allergen.name;
+          
+          return (
+            <label
+              key={allergen.id}
+              className={`flex items-center space-x-3 p-3 rounded-md border cursor-pointer transition-colors min-h-[44px] ${
+                isSelected 
+                  ? 'bg-primary text-white border-primary' 
+                  : 'bg-white hover:bg-gray-50 border-gray-200'
+              }`}
+            >
+              <input
+                type="checkbox"
+                checked={isSelected}
+                onChange={() => handleToggle(allergen.id)}
+                className="hidden"
+                aria-describedby={`allergen-${allergen.id}-description`}
+              />
+              
+              <span 
+                className={`flex-shrink-0 w-6 h-6 flex items-center justify-center text-xs font-bold rounded ${
+                  isSelected ? 'bg-white text-primary' : 'bg-danger text-white'
+                }`}
+                aria-hidden="true"
+              >
+                {allergen.id}
+              </span>
+              
+              <span className="flex-1 text-sm font-medium">
+                {displayName}
+              </span>
+              
+              <span 
+                id={`allergen-${allergen.id}-description`}
+                className="sr-only"
+              >
+                Allergen {allergen.id}: {displayName}
+              </span>
+            </label>
+          );
+        })}
+      </div>
+      
+      {selectedIds.length > 0 && (
+        <div className="mt-4 p-3 bg-gray-50 rounded-md">
+          <p className="text-sm text-gray-600">
+            <strong>Ausgewählte Allergene:</strong>{' '}
+            {selectedIds.sort().join(', ')}
+          </p>
+        </div>
+      )}
+    </fieldset>
+  );
+}