feat(admin): implement unified submission and newsletter management

Introduce a centralized system to manage all website form submissions and newsletter subscriptions.
- Add `Submission` and `NewsletterSubscription` models with MongoDB schema validation
- Implement `submissionController` and `newsletterSubscriptionController` for CRUD operations and filtering
- Create a unified admin UI for reviewing submissions across different sources (home, request, contact, partnership, newsletter)
- Add database migration scripts for creating collections and indexes
- Refactor partnership inquiry forms to use a fixed field structure
- Update admin navigation and server CORS settings to support PATCH requests

views/admin/partnerships/partials/editor-script.ejs

@@ -97,12 +97,6 @@
       renderPartners();
     });
 
-    document.getElementById("addInquiryFieldBtn")?.addEventListener("click", function () {
-      state.inquiryForm.fields.push(getDefaultInquiryField());
-      ensurePartnershipIds();
-      renderInquiryFields();
-    });
-
     document.getElementById("resetPartnershipsForm")?.addEventListener("click", function () {
       window.location.reload();
     });
@@ -378,7 +372,7 @@
         input.value = field[key] || "";
         input.addEventListener("input", function () {
           field[key] = input.value;
-            if (key === "label") {
+          if (key === "label") {
             title.textContent = input.value || `${inquiryFieldFields.label?.label || "Field"} ${index + 1}`;
           }
           if (key === "type") {
@@ -401,11 +395,6 @@
         }
       });
 
-      node.querySelector("[data-remove-item]").addEventListener("click", function () {
-        state.inquiryForm.fields.splice(index, 1);
-        renderInquiryFields();
-      });
-
       node.querySelector("[data-add-option]").addEventListener("click", function () {
         field.options = Array.isArray(field.options) ? field.options : [];
         field.options.push("");
@@ -444,7 +433,6 @@
       inquiryFieldsList.appendChild(node);
     });
 
-    initSortable(inquiryFieldsList, state.inquiryForm.fields, renderInquiryFields, '[data-item="inquiry-field"]');
   }
 
   function initSortable(container, list, rerender, draggableSelector) {