Remove double flags for bookmarks

- Remove the double flag if a checkpoint exists
- Add the "replace checkpoint" functionality as a Shift+Click option to the checkpoint flag

public/index.html

@@ -5777,7 +5777,7 @@
                                 <div title="Create branch" class="mes_button mes_create_branch fa-regular fa-code-branch" data-i18n="[title]Create Branch"></div>
                                 <div title="Copy" class="mes_button mes_copy fa-solid fa-copy " data-i18n="[title]Copy"></div>
                             </div>
-                            <div title="Open checkpoint chat" class="mes_button mes_bookmark fa-solid fa-flag" data-i18n="[title]Open checkpoint chat"></div>
+                            <div title="Open checkpoint chat&#13;&#13;Shift+Click to replace the existing checkpoint with a new one" class="mes_button mes_bookmark fa-solid fa-flag" data-i18n="[title]Open checkpoint chat&#13;&#13;Shift+Click to replace the existing checkpoint with a new one"></div>
                             <div title="Edit" class="mes_button mes_edit fa-solid fa-pencil " data-i18n="[title]Edit"></div>
                         </div>
                         <div class="mes_edit_buttons">

public/script.js

@@ -10563,7 +10563,14 @@ jQuery(async function () {
         await duplicateCharacter();
     });
 
-    $(document).on('click', '.select_chat_block, .bookmark_link, .mes_bookmark', async function () {
+    $(document).on('click', '.select_chat_block, .bookmark_link, .mes_bookmark', async function (e) {
+        // If shift is held down, we are not following the bookmark, but creating a new one
+        if (e.shiftKey) {
+            var selectedMesId = $(this).closest('.mes').attr('mesid');
+            createNewBookmark(selectedMesId);
+            return;
+        }
+
         let file_name = $(this).hasClass('mes_bookmark')
             ? $(this).closest('.mes').attr('bookmark_link')
             : $(this).attr('file_name').replace('.jsonl', '');

public/style.css

@@ -3963,6 +3963,10 @@ input[type="range"]::-webkit-slider-thumb {
     display: inline-block;
 }
 
+.mes:not([bookmark_link='']) .mes_create_bookmark {
+    display: none;
+}
+
 .mes_edit_buttons {
     display: none;
     flex-direction: row;