feat(meals): add optional recipe link to meal cards (#18)

- New optional recipe_url field in the meal modal (below Notes)
- Link icon appears on meal cards when a URL is set, opens in new tab
- DB migration v6: ALTER TABLE meals ADD COLUMN recipe_url TEXT
- API: recipe_url supported in POST /meals and PUT /meals/:id
- i18n: new keys recipeUrlLabel, recipeUrlPlaceholder, openRecipe (de, en, sv, it)

public/pages/meals.js

@@ -219,6 +219,13 @@ function renderSlot(date, type, mealsForDay) {
           <span class="meal-card__ingredients-count">${ingLabel}${esc(ingDoneLabel)}</span>
         </div>` : ''}
         <div class="meal-card__actions">
+          ${meal.recipe_url ? `<a class="meal-card__action-btn meal-card__action-btn--recipe"
+            data-action="open-recipe"
+            href="${esc(meal.recipe_url)}"
+            target="_blank"
+            rel="noopener noreferrer"
+            aria-label="${t('meals.openRecipe')}"
+          ><i data-lucide="link" style="width:14px;height:14px;" aria-hidden="true"></i></a>` : ''}
           ${canTransfer ? `<button class="meal-card__action-btn meal-card__action-btn--shopping"
             data-action="transfer-meal"
             data-meal-id="${meal.id}"
@@ -270,6 +277,12 @@ function wireGrid(grid) {
       return;
     }
 
+    if (action === 'open-recipe') {
+      // Link öffnet sich nativ - nur Bubbling stoppen damit kein Edit-Modal aufgeht
+      e.stopPropagation();
+      return;
+    }
+
     if (action === 'edit-meal') {
       const mealId = parseInt(btn.dataset.mealId, 10);
       const meal   = state.meals.find((m) => m.id === mealId);
@@ -310,7 +323,7 @@ function wireDragDrop(grid) {
   grid.addEventListener('pointerdown', (e) => {
     const card = e.target.closest('.meal-card');
     if (!card) return;
-    if (e.target.closest('[data-action="delete-meal"], [data-action="transfer-meal"]')) return;
+    if (e.target.closest('[data-action="delete-meal"], [data-action="transfer-meal"], [data-action="open-recipe"]')) return;
 
     const slot = card.closest('.meal-slot');
     if (!slot) return;
@@ -573,6 +586,13 @@ function buildModalContent({ mode, date, mealType, meal }) {
                 placeholder="${t('meals.notesPlaceholder')}">${esc(isEdit && meal.notes ? meal.notes : '')}</textarea>
     </div>
 
+    <div class="form-group">
+      <label class="form-label" for="modal-recipe-url">${t('meals.recipeUrlLabel')}</label>
+      <input type="url" class="form-input" id="modal-recipe-url"
+             placeholder="${t('meals.recipeUrlPlaceholder')}"
+             value="${esc(isEdit && meal.recipe_url ? meal.recipe_url : '')}">
+    </div>
+
     <div class="form-group">
       <label class="form-label">${t('meals.ingredientsLabel')}</label>
       <div class="ingredient-list" id="ingredient-list">${ingRows}</div>
@@ -623,6 +643,7 @@ async function saveModal(overlay) {
   const meal_type = overlay.querySelector('#modal-type').value;
   const title     = overlay.querySelector('#modal-title').value.trim();
   const notes     = overlay.querySelector('#modal-notes').value.trim() || null;
+  const recipe_url = overlay.querySelector('#modal-recipe-url').value.trim() || null;
 
   if (!title) {
     window.oikos?.showToast(t('meals.titleRequired'), 'error');
@@ -643,11 +664,11 @@ async function saveModal(overlay) {
     const { mode, meal } = state.modal;
 
     if (mode === 'create') {
-      const res     = await api.post('/meals', { date, meal_type, title, notes, ingredients });
+      const res     = await api.post('/meals', { date, meal_type, title, notes, recipe_url, ingredients });
       state.meals.push(res.data);
     } else {
       // Update meal meta
-      await api.put(`/meals/${meal.id}`, { date, meal_type, title, notes });
+      await api.put(`/meals/${meal.id}`, { date, meal_type, title, notes, recipe_url });
 
       // Sync ingredients
       const existingIds = new Set((meal.ingredients ?? []).map((i) => i.id));