fix: page mode toggle no longer overwrites default preference (#1996)

The header edit/read toggle now controls only the current session's mode
without saving it as the user's preference. The saved preference (set in
profile settings) is applied once on initial load and sticks across page
navigations within the session, so navigating to a new page no longer
resets the mode mid-session.

Fixes #1693

apps/client/src/features/editor/full-editor.tsx

@@ -1,5 +1,5 @@
 import classes from "@/features/editor/styles/editor.module.css";
-import React from "react";
+import React, { useEffect } from "react";
 import { TitleEditor } from "@/features/editor/title-editor";
 import PageEditor from "@/features/editor/page-editor";
 import {
@@ -24,6 +24,7 @@ import { FixedToolbar } from "@/features/editor/components/fixed-toolbar/fixed-t
 import { PageEditMode } from "@/features/user/types/user.types.ts";
 import useToggleAside from "@/hooks/use-toggle-aside.tsx";
 import clsx from "clsx";
+import { currentPageEditModeAtom } from "@/features/editor/atoms/editor-atoms.ts";
 
 const MemoizedTitleEditor = React.memo(TitleEditor);
 const MemoizedPageEditor = React.memo(PageEditor);
@@ -34,6 +35,10 @@ type PageCreator = {
   avatarUrl: string;
 };
 
+// Module-level flag: survives component unmount/remount on page navigation,
+// reset only on full page reload (i.e. a new app session).
+let defaultEditModeApplied = false;
+
 export interface FullEditorProps {
   pageId: string;
   slugId: string;
@@ -61,9 +66,19 @@ export function FullEditor({
   const fullPageWidth = user.settings?.preferences?.fullPageWidth;
   const editorToolbarEnabled =
     user.settings?.preferences?.editorToolbar ?? false;
+  const [currentPageEditMode, setCurrentPageEditMode] = useAtom(currentPageEditModeAtom);
   const userPageEditMode =
     user.settings?.preferences?.pageEditMode ?? PageEditMode.Edit;
-  const isEditMode = userPageEditMode === PageEditMode.Edit;
+  const isEditMode = currentPageEditMode === PageEditMode.Edit;
+
+  // Apply the user's saved preference only once on initial load, not on every
+  // page navigation — so the mode sticks across navigations within a session.
+  useEffect(() => {
+    if (!defaultEditModeApplied) {
+      setCurrentPageEditMode(userPageEditMode);
+      defaultEditModeApplied = true;
+    }
+  }, [userPageEditMode, setCurrentPageEditMode]);
 
   return (
     <Container