Library: "Continue where you left off" row with a per-user setting

One fixed row above the library showing the five most recently read,
unfinished manga with the normal tiles (they stay in the grid as well).
It ignores search and filters, hides while sorted by "Recently read",
and can be turned off under Settings > Reading > Library page
(continueRow, default on).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

server.js

@@ -111,7 +111,7 @@ function checkPw(pw, stored) {
 }
 const DUMMY_HASH = hashPw('x');
 const DEFAULTS = { startMode: 'last', lastMode: 'page', adapt: true, skipExtras: false, skipCovers: false, flowPageGap: true, pageTone: 'original', readingClock: false, readingStory: true,
-  readDate: 'hour', releaseDate: true, discoveryEnabled: false, discoveryReadingActivity: false, discoveryMature: false, zoom: {}, webhook: '' };
+  continueRow: true, readDate: 'hour', releaseDate: true, discoveryEnabled: false, discoveryReadingActivity: false, discoveryMature: false, zoom: {}, webhook: '' };
 const settingsOf = u => ({ ...DEFAULTS, ...u.settings, zoom: { ...(u.settings && u.settings.zoom) } });
 
 function createUser(name, pw, admin, replace) {
@@ -530,7 +530,7 @@ const routes = {
     if (['flow', 'page', 'book'].includes(b.lastMode)) s.lastMode = b.lastMode;
     if (['original', 'inverted', 'sepia', 'dim', 'extra-dim'].includes(b.pageTone)) s.pageTone = b.pageTone;
     if (['off', 'date', 'hour'].includes(b.readDate)) s.readDate = b.readDate;
-    for (const k of ['adapt', 'skipExtras', 'skipCovers', 'flowPageGap', 'readingClock', 'readingStory', 'releaseDate',
+    for (const k of ['adapt', 'skipExtras', 'skipCovers', 'flowPageGap', 'readingClock', 'readingStory', 'releaseDate', 'continueRow',
       'discoveryEnabled', 'discoveryReadingActivity', 'discoveryMature']) if (typeof b[k] === 'boolean') s[k] = b[k];
     if (b.zoom && typeof b.zoom === 'object') {
       s.zoom = {};