fix(webui): address Migrate-refactor review findings

- Restore empty-state 'Open Locations' now deep-links to the backup center's
  Locations sub-tab: the embedded center honors /overview/backups/<sub> and
  switchTab()s to it after mount (was landing on Dashboard).
- PeersPage.notify + MigratePage.notify use the real window.notificationSystem
  (were calling a never-defined window.showNotification → console-only).
- Remove the now-dead Admin config-manager peers branch (Peers left Admin).
- Trim the dead migrate.json/peers fetch + hostnameToPeerName from BackupPage
  (no consumer after the migrate removal).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

containers/libreportal/frontend/components/admin/config/js/config-manager.js

@@ -72,24 +72,8 @@ if (typeof window.ConfigManager === 'undefined') {
       // instances (kind=backup-channel for shared-backup migrate, or
       // kind=direct-ssh-direct for live SSH pulls). Same shape as SSH Access:
       // we inject its content template, then init PeersPage.
-      if (category === 'peers') {
+      // Peers moved out of Admin → Overview › Migrate › Peers; /admin/tools/peers
-        try { this.sidebar.populateSidebar(); } catch (e) {}
+      // redirects there, so this branch is intentionally gone.
-        await lazyLoad('/components/admin/peers/js/peers-page.js');
-        try {
-          const html = await fetch('/components/admin/peers/html/peers-content.html').then(r => r.text());
-          configSection.innerHTML = html;
-        } catch (e) {
-          configSection.innerHTML = '<div class="error">Peers page template failed to load.</div>';
-          return;
-        }
-        if (typeof PeersPage !== 'undefined') {
-          window.peersPage = new PeersPage('config-section');
-          await window.peersPage.init();
-        } else {
-          configSection.innerHTML = '<div class="error">PeersPage controller not loaded.</div>';
-        }
-        return;
-      }
 
       // System is an admin tool page that internally routes between index /
       // metric / per-app / storage sub-views based on the URL sub-path.

containers/libreportal/frontend/components/admin/peers/js/peers-page.js

@@ -431,7 +431,7 @@ class PeersPage {
     }
 
     notify(message, kind) {
-        if (typeof window.showNotification === 'function') window.showNotification(message, kind);
+        if (window.notificationSystem && window.notificationSystem.show) window.notificationSystem.show(message, kind || 'info');
         else if (kind === 'error') console.error(message);
         else console.log(message);
     }

containers/libreportal/frontend/components/apps/overview/js/overview-manager.js

@@ -428,17 +428,26 @@ class OverviewManager {
   // configuration sections (its sidebar restyled as a nested tab strip). On a
   // revisit we refresh rather than re-mount, to keep its sub-tab + expand state.
   mountBackupCenter(pane) {
+    // Honor an optional sub-tab deep-link (/overview/backups/<sub>), e.g. the
+    // Restore empty-state's "Open Locations" button.
+    const seg = window.location.pathname.replace(/^\/overview\/backups\/?/, '').split('/')[0];
+    const sub = ['dashboard', 'backups', 'locations', 'configuration'].includes(seg) ? seg : null;
     // Detect a prior mount by the embedded fragment in THIS pane — not by
     // #backup-section, which the per-app Backups tab also defines.
     if (pane.querySelector('.backup-layout') && window.overviewBackupPage) {
-      try { window.overviewBackupPage.refreshAll().then(() => window.overviewBackupPage.render()).catch(() => {}); } catch (_) {}
+      try {
+        window.overviewBackupPage.refreshAll().then(() => {
+          window.overviewBackupPage.render();
+          if (sub) window.overviewBackupPage.switchTab(sub);
+        }).catch(() => {});
+      } catch (_) {}
       return;
     }
     pane.innerHTML = '<div class="updater-empty">Loading backup center…</div>';
-    this._loadBackupCenter(pane);
+    this._loadBackupCenter(pane, sub);
   }
 
-  async _loadBackupCenter(pane) {
+  async _loadBackupCenter(pane, sub) {
     if (this._backupLoading) return;
     this._backupLoading = true;
     try {
@@ -456,6 +465,7 @@ class OverviewManager {
       try { if (window.overviewBackupPage) window.overviewBackupPage.dispose(); } catch (_) {}
       window.overviewBackupPage = new BackupPage({ embedded: true });
       await window.overviewBackupPage.init();
+      if (sub) { try { window.overviewBackupPage.switchTab(sub); } catch (_) {} }
     } catch (_) {
       pane.innerHTML = '<div class="updater-empty">Failed to load the backup center.</div>';
     } finally {

containers/libreportal/frontend/components/apps/overview/migrate/js/migrate-page.js

@@ -68,7 +68,7 @@ class MigratePage {
       }
       const locBtn = e.target.closest('[data-action="go-to-locations"]');
       if (locBtn && this.root()?.contains(locBtn)) {
-        if (window.navigateToRoute) window.navigateToRoute('/overview/backups');
+        if (window.navigateToRoute) window.navigateToRoute('/overview/backups/locations');
         return;
       }
       if (e.target.closest('#ov-migrate-confirm')) { this.confirmMigrate(); return; }
@@ -107,8 +107,9 @@ class MigratePage {
   closeModal() { document.getElementById('ov-migrate-modal')?.classList.remove('open'); }
 
   notify(msg, type) {
-    const n = (window.LP && window.LP.services && window.LP.services.notify) || window.notify;
+    if (window.notificationSystem && window.notificationSystem.show) window.notificationSystem.show(msg, type || 'info');
-    if (n && n.show) n.show(msg, type || 'info');
+    else if (type === 'error') console.error(msg);
+    else console.log(msg);
   }
 
   async runTask(command, type, app) {

containers/libreportal/frontend/components/backup/core/js/backup-fetch-client.js

@@ -2,26 +2,17 @@
 Object.assign(BackupPage.prototype, {
     async refreshAll() {
         const ts = Date.now();
-        const [dashboard, locations, , schema, migrate, peersData] = await Promise.all([
+        const [dashboard, locations, , schema] = await Promise.all([
             this.fetchJson(`/data/backup/generated/dashboard.json?t=${ts}`),
             this.fetchJson(`/data/backup/generated/locations.json?t=${ts}`),
             this.loadSystemConfigs(),
-            this.fetchJson(`/data/backup/generated/schema.json?t=${ts}`),
+            this.fetchJson(`/data/backup/generated/schema.json?t=${ts}`)
-            this.fetchJson(`/data/backup/generated/migrate.json?t=${ts}`),
-            this.fetchJson(`/data/peers/generated/peers.json?t=${ts}`)
         ]);
         this.dashboard = dashboard;
         this.locations = locations;
         this.locSchema = schema;
-        this.migrate = migrate;
+        // (migrate.json + peers lookup moved to MigratePage when Migrate left the
-        // Build hostname → friendly-name lookup once so renderMigrate can show
+        // backup center — nothing here consumes them anymore.)
-        // "homelab (host: homelab.lan)" instead of bare hostnames.
-        this.hostnameToPeerName = {};
-        for (const p of (peersData?.peers || [])) {
-            if (p.kind === 'backup-channel' && p.config?.hostname) {
-                this.hostnameToPeerName[p.config.hostname] = p.name;
-            }
-        }
         this.snapshotsByLoc = {};
 
         if (!this.engines.length) await this.loadEngines();