feat(subscription): Add comments for subscriptions

Close #3

src/meal_manager/templates/subscribe.html

@@ -89,6 +89,17 @@
                                     {% endfor %}
                                 </div>
                             </div>
+
+                            <div class="mb-3">
+                                <label class="form-label">Kommentar</label>
+                                <p class="text-muted small mb-2">
+                                    Dieser Kommentar wird bei jeder Anmeldung hinzugefügt.
+                                </p>
+                                <div class="d-flex flex-wrap gap-3">
+                                    <input name="comment" id="InputComment" class="form-control"
+                                  aria-label="Kommentar">
+                                </div>
+                            </div>
                         </div>
 
                         <!-- Footer -->
@@ -134,6 +145,14 @@
                         <div class="fw-bold small">{{ sub.day_string_de() }}</div>
                     </div>
                 </div>
+                {% if sub.comment %}
+                <div class="row g-2">
+                   <div class="col-12">
+                        <div class="text-muted" style="font-size: 0.7rem;">Kommentar</div>
+                        <div class="fw-bold small">{{ sub.comment }}</div>
+                    </div>
+                </div>
+                {% endif %}
             </div>
         </div>
         {% endfor %}