refactor(ui): standardize button types and migrate file operations to V3 Action API

src/routes/events/+layout.svelte

@@ -124,7 +124,7 @@
 
 {#if $events_loc?.ver && $events_loc?.ver !== $events_sess?.ver}
     <div class="fixed inset-0 bg-pink-100/80 z-40">
-        <button
+        <button type="button"
             class="
             fixed top-16 left-0 right-0 z-50 p-4 m-8 sm:mx-16 md:mx-32
             btn btn-lg rounded-2xl
@@ -269,8 +269,7 @@
         "
     >
         <!-- Scroll to top button -->
-        <button
-            type="button"
+        <button type="button"
             class="
             ae_btn_success_outlined
 
@@ -299,8 +298,7 @@
         </button>
 
         <!-- Scroll to bottom button -->
-        <button
-            type="button"
+        <button type="button"
             class="
             ae_btn_success_outlined