refactor: simplify editor scroll logic

- Extract `scrollToCaret` helper to deduplicate scroll logic
- Unify precise scroll behavior for both manual triggers and auto-scroll

web/src/components/MemoEditor/Editor/index.tsx

@@ -52,6 +52,26 @@ const Editor = forwardRef(function Editor(props: EditorProps, ref: React.Forward
     }
   }, [handleContentChangeCallback, updateEditorHeight]);
 
+  const scrollToCaret = useCallback((options: { force?: boolean } = {}) => {
+    const editor = editorRef.current;
+    if (!editor) return;
+
+    const { force = false } = options;
+    const caret = getCaretCoordinates(editor, editor.selectionEnd);
+
+    if (force) {
+      editor.scrollTop = Math.max(0, caret.top - editor.clientHeight / 2);
+      return;
+    }
+
+    const lineHeight = parseFloat(getComputedStyle(editor).lineHeight) || 24;
+    const viewportBottom = editor.scrollTop + editor.clientHeight;
+    // Scroll if cursor is near or beyond bottom edge (within 2 lines)
+    if (caret.top + lineHeight * 2 > viewportBottom) {
+      editor.scrollTop = Math.max(0, caret.top - editor.clientHeight / 2);
+    }
+  }, []);
+
   useEffect(() => {
     if (editorRef.current && initialContent) {
       editorRef.current.value = initialContent;
@@ -75,12 +95,7 @@ const Editor = forwardRef(function Editor(props: EditorProps, ref: React.Forward
       getEditor: () => editorRef.current,
       focus: () => editorRef.current?.focus(),
       scrollToCursor: () => {
-        const editor = editorRef.current;
-        if (!editor) return;
-
-        const caret = getCaretCoordinates(editor, editor.selectionEnd);
-        // Scroll to center cursor vertically
-        editor.scrollTop = Math.max(0, caret.top - editor.clientHeight / 2);
+        scrollToCaret({ force: true });
       },
       insertText: (content = "", prefix = "", suffix = "") => {
         const editor = editorRef.current;
@@ -143,7 +158,7 @@ const Editor = forwardRef(function Editor(props: EditorProps, ref: React.Forward
         updateContent();
       },
     }),
-    [updateContent],
+    [updateContent, scrollToCaret],
   );
 
   useImperativeHandle(ref, () => editorActions, [editorActions]);
@@ -155,18 +170,9 @@ const Editor = forwardRef(function Editor(props: EditorProps, ref: React.Forward
 
       // Auto-scroll to keep cursor visible when typing
       // See: https://github.com/usememos/memos/issues/5469
-      const editor = editorRef.current;
-      const caret = getCaretCoordinates(editor, editor.selectionEnd);
-      const lineHeight = parseFloat(getComputedStyle(editor).lineHeight) || 24;
-
-      // Scroll if cursor is near or beyond bottom edge (within 2 lines)
-      const viewportBottom = editor.scrollTop + editor.clientHeight;
-      if (caret.top + lineHeight * 2 > viewportBottom) {
-        // Scroll to center cursor vertically
-        editor.scrollTop = Math.max(0, caret.top - editor.clientHeight / 2);
-      }
+      scrollToCaret();
     }
-  }, [handleContentChangeCallback, updateEditorHeight]);
+  }, [handleContentChangeCallback, updateEditorHeight, scrollToCaret]);
 
   // Auto-complete markdown lists when pressing Enter
   useListCompletion({