fix: restore text paste in message editor (Quill)

The clipboard.onPaste override broke text pasting in Quill 2.x
where this internal API is no longer public. Replaced with a DOM
paste event listener on quill.root that only intercepts image
pastes and lets Quill handle text paste natively.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

static/js/conversations.js

@@ -1289,23 +1289,22 @@
                 input.click();
             });
 
-            // Intercept paste at Quill's clipboard module level
-            var originalPaste = state.quill.clipboard.onPaste;
-            state.quill.clipboard.onPaste = function(e) {
+            // Intercept paste — only handle images, let Quill handle text natively
+            state.quill.root.addEventListener('paste', function(e) {
                 var clipboardData = e.clipboardData || window.clipboardData;
                 if (clipboardData && clipboardData.items) {
                     for (var i = 0; i < clipboardData.items.length; i++) {
                         if (clipboardData.items[i].type.indexOf('image') !== -1) {
                             e.preventDefault();
+                            e.stopPropagation();
                             var file = clipboardData.items[i].getAsFile();
                             if (file) Composer.uploadAndInsertImage(file);
-                            return; // Don't call original paste
+                            return;
                         }
                     }
                 }
-                // No image — let Quill handle text paste normally
-                if (originalPaste) originalPaste.call(this, e);
-            };
+                // Text paste — do nothing, Quill handles it natively
+            }, true);
 
             // Typing indicator
             state.quill.on('text-change', function () {

templates/messages/conversations.html

@@ -326,7 +326,7 @@ window.__CSRF_TOKEN__ = '{{ csrf_token() }}';
 // Load conversations.js after data is set
 (function() {
     var s = document.createElement('script');
-    s.src = '{{ url_for("static", filename="js/conversations.js") }}?v=27';
+    s.src = '{{ url_for("static", filename="js/conversations.js") }}?v=28';
     document.body.appendChild(s);
 })();
 {% endblock %}