Preserve platform tab route state

Remember each primary platform tab's last route so URL-backed filters survive tab switches without leaking query state across tabs.

docs/release-control/v6/internal/subsystems/ai-runtime.md

@@ -3429,6 +3429,12 @@ Intelligence > Provider & Models route
 route remains a compatibility alias for old deep links, not a href emitted by
 new Assistant provider-repair actions.
 
+Primary platform route memory in `frontend-modern/src/AppLayout.tsx` may
+preserve platform-local query state such as workload filters, but that memory
+remains navigation chrome only. It must not fork Assistant drawer state, Patrol
+utility route state, prompt context, resource reads, commercial posture, or
+cross-platform query parameters.
+
 Rejected Patrol investigation-fix approvals are terminal governed-action
 decisions in the AI runtime. `/api/ai/approvals/{id}/deny` must persist the
 approval-store denial, record a rejected unified action-audit decision when the

docs/release-control/v6/internal/subsystems/cloud-paid.md

@@ -826,6 +826,13 @@ or other self-hosted uncapped continuity plans.
     existing Patrol findings and live-approval read model after authentication;
     it must not read hosted billing state, trigger commercial-posture loading,
     affect organization visibility, or become an upgrade/acquisition cue.
+    The same primary platform navigation must remember the last in-tab route
+    state per platform, including query and hash, so route-owned filters such
+    as Proxmox workload status survive switching to another platform tab and
+    back. That memory is chrome route state only: it must validate the route
+    still belongs to the selected platform before reuse and must not become
+    hosted org bootstrap, entitlement, billing, acquisition, or cross-platform
+    query state.
     The same AppLayout shell may contextualize the closed Pulse Assistant
     launcher around the current monitoring, Patrol, Alerts, or Settings route,
     but that launcher must remain a local product affordance. It must not read

frontend-modern/src/AppLayout.tsx

@@ -31,6 +31,12 @@ import { logger } from '@/utils/logger';
 import { getActiveTabForPath } from '@/routing/navigation';
 import { preloadRouteModule } from '@/routing/routePreload';
 import {
+  DOCKER_PATH,
+  KUBERNETES_PATH,
+  PROXMOX_PATH,
+  STANDALONE_PATH,
+  TRUENAS_PATH,
+  VMWARE_PATH,
   buildDockerPath,
   buildKubernetesPath,
   buildProxmoxPath,
@@ -56,12 +62,54 @@ const ROOT_VMWARE_PATH = buildVmwarePath();
 const ROOT_STANDALONE_PATH = buildStandalonePath();
 const ROOT_INFRASTRUCTURE_SETTINGS_PATH = buildInfrastructureWorkspacePath();
 const ROOT_ALERTS_PATH = '/alerts';
+const PRIMARY_ROUTE_PREFIX_BY_ID: Record<PrimaryPlatformNavId, string> = {
+  proxmox: PROXMOX_PATH,
+  docker: DOCKER_PATH,
+  kubernetes: KUBERNETES_PATH,
+  truenas: TRUENAS_PATH,
+  vmware: VMWARE_PATH,
+  standalone: STANDALONE_PATH,
+};
+type PrimaryRouteMemory = Partial<Record<PrimaryPlatformNavId, string>>;
+let primaryRouteMemory: PrimaryRouteMemory = {};
 
 function resolveStandaloneSubTabTitle(pathname: string): string {
   const normalized = pathname.replace(/\/+$/, '');
   if (normalized === buildStandalonePath('availability')) return 'Availability checks';
   return 'Machines';
 }
+
+function routeBelongsToPrimaryTab(route: string, tabId: PrimaryPlatformNavId): boolean {
+  const prefix = PRIMARY_ROUTE_PREFIX_BY_ID[tabId];
+  const pathname = route.split(/[?#]/, 1)[0]?.replace(/\/+$/, '') || '/';
+  return pathname === prefix || pathname.startsWith(`${prefix}/`);
+}
+
+function isPrimaryPlatformNavId(tabId: string | null | undefined): tabId is PrimaryPlatformNavId {
+  return Boolean(tabId && tabId in PRIMARY_ROUTE_PREFIX_BY_ID);
+}
+
+function currentPrimaryRoute(pathname: string, search: string, hash: string): string {
+  return `${pathname}${search}${hash}`;
+}
+
+function resolvePrimaryNavigationRoute(
+  tab: PrimaryTab,
+  routeMemory: PrimaryRouteMemory,
+): string {
+  if (!tab.enabled) {
+    return tab.settingsRoute;
+  }
+  const remembered = routeMemory[tab.id as PrimaryPlatformNavId];
+  if (remembered && routeBelongsToPrimaryTab(remembered, tab.id as PrimaryPlatformNavId)) {
+    return remembered;
+  }
+  return tab.route;
+}
+
+export function resetPrimaryNavigationRouteMemory() {
+  primaryRouteMemory = {};
+}
 const NAV_TAB_ICON_CLASS = 'w-4 h-4 shrink-0';
 const AI_CHAT_LAUNCHER_BUTTON_CLASS =
   'fixed right-4 bottom-[calc(5rem+env(safe-area-inset-bottom,0px))] z-40 flex h-11 w-11 items-center justify-center rounded-full border border-border bg-surface text-blue-600 shadow-lg transition-colors duration-200 hover:bg-surface-hover hover:text-blue-700 focus-visible:outline focus-visible:outline-2 focus-visible:outline-offset-2 focus-visible:outline-blue-500 dark:text-blue-400 dark:hover:text-blue-300 lg:right-0 lg:top-1/2 lg:bottom-auto lg:h-auto lg:w-auto lg:min-h-9 lg:min-w-10 lg:-translate-y-1/2 lg:rounded-l-lg lg:rounded-r-none lg:border-r-0 lg:px-2.5 lg:py-2.5 lg:shadow-none';
@@ -258,6 +306,15 @@ export function AppLayout(props: AppLayoutProps) {
     return navId ? primaryInfrastructureRouteById[navId] : ROOT_ALERTS_PATH;
   });
 
+  createEffect(() => {
+    const activeTab = getActiveTabForPath(location.pathname);
+    if (!isPrimaryPlatformNavId(activeTab)) return;
+    const route = currentPrimaryRoute(location.pathname, location.search, location.hash);
+    if (!routeBelongsToPrimaryTab(route, activeTab)) return;
+    if (primaryRouteMemory[activeTab] === route) return;
+    primaryRouteMemory = { ...primaryRouteMemory, [activeTab]: route };
+  });
+
   createEffect(() => {
     if (kioskMode()) {
       setHeaderVisible(true);
@@ -483,7 +540,7 @@ export function AppLayout(props: AppLayoutProps) {
   });
 
   const handlePrimaryClick = (tab: PrimaryTab) => {
-    const targetRoute = tab.enabled ? tab.route : tab.settingsRoute;
+    const targetRoute = resolvePrimaryNavigationRoute(tab, primaryRouteMemory);
     void (async () => {
       try {
         await preloadRouteModule(targetRoute);
@@ -521,10 +578,7 @@ export function AppLayout(props: AppLayoutProps) {
   };
 
   const getPrimaryTargetRoute = (tab: PrimaryTab) => {
-    if (tab.enabled) {
+    return resolvePrimaryNavigationRoute(tab, primaryRouteMemory);
-      return tab.route;
-    }
-    return tab.settingsRoute;
   };
 
   const renderPrimaryNavigationTab = (tab: PrimaryTab) => {

frontend-modern/src/__tests__/App.architecture.test.ts

@@ -237,6 +237,12 @@ describe('App architecture', () => {
     expect(appLayoutSource).toContain('settingsRoute: ROOT_INFRASTRUCTURE_SETTINGS_PATH');
     expect(appLayoutSource).not.toContain("settingsRoute: '/settings/workloads");
     expect(appLayoutSource).not.toContain("settingsRoute: '/settings/infrastructure/platforms");
+    expect(appLayoutSource).toContain('type PrimaryRouteMemory = Partial');
+    expect(appLayoutSource).toContain('let primaryRouteMemory: PrimaryRouteMemory = {};');
+    expect(appLayoutSource).toContain('function resolvePrimaryNavigationRoute(');
+    expect(appLayoutSource).toContain('routeBelongsToPrimaryTab(remembered');
+    expect(appLayoutSource).not.toContain('primaryRouteMemory[props.activeOrgID');
+    expect(appLayoutSource).not.toContain('primaryRouteMemory[activeOrgID');
     expect(appLayoutSource).toContain('<OrgSwitcher');
     expect(appLayoutSource).toContain('const status = () => props.connectionStatus();');
     expect(appLayoutSource).toContain(

frontend-modern/src/__tests__/AppLayout.test.tsx

@@ -3,10 +3,11 @@ import { Route, Router } from '@solidjs/router';
 import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
 import type { State } from '@/types/api';
 import type { Resource } from '@/types/resource';
-import { AppLayout } from '@/AppLayout';
+import { AppLayout, resetPrimaryNavigationRouteMemory } from '@/AppLayout';
 import { aiChatStore } from '@/stores/aiChat';
 
 HTMLElement.prototype.scrollIntoView = vi.fn();
+window.scrollTo = vi.fn();
 
 const aiIntelligenceMockState = vi.hoisted(() => ({
   patrolOpenWorkCount: 0,
@@ -20,9 +21,14 @@ vi.mock('@/stores/aiIntelligence', () => ({
   },
 }));
 
+vi.mock('@/routing/routePreload', () => ({
+  preloadRouteModule: vi.fn(() => Promise.resolve()),
+}));
+
 describe('AppLayout navigation icons', () => {
   beforeEach(() => {
     window.history.replaceState({}, '', '/settings/infrastructure');
+    resetPrimaryNavigationRouteMemory();
     aiIntelligenceMockState.patrolOpenWorkCount = 0;
     aiChatStore.close();
     aiChatStore.setEnabled(true);
@@ -48,51 +54,65 @@ describe('AppLayout navigation icons', () => {
       ...overrides,
     }) as Resource;
 
-  const renderLayout = (resources: Resource[] = []) =>
+  const renderLayout = (resources: Resource[] = [], initialPath = '/settings/infrastructure') => {
-    render(() => (
+    window.history.replaceState({}, '', initialPath);
+    const LayoutRoute = () => (
+      <AppLayout
+        connectionStatus={() => ({
+          kind: 'connected',
+          label: 'Connected',
+          detail: 'Backend and live data stream are connected.',
+          tone: 'healthy',
+        })}
+        lastUpdateText={() => ''}
+        versionInfo={() =>
+          ({
+            version: '6.0.0-rc.2',
+            channel: 'rc',
+            isDevelopment: false,
+            isDocker: false,
+          }) as never
+        }
+        hasAuth={() => true}
+        needsAuth={() => false}
+        proxyAuthInfo={() => null}
+        handleLogout={() => {}}
+        state={() =>
+          ({
+            activeAlerts: [{ id: 'alert-1', level: 'warning', acknowledged: false }],
+            resources,
+          }) as unknown as State
+        }
+        tokenScopes={() => ['settings:read']}
+        organizations={() => []}
+        activeOrgID={() => 'default'}
+        orgsLoading={() => false}
+        showOrgSwitcher={() => false}
+        onSwitchOrg={() => {}}
+      >
+        <div>Infrastructure body</div>
+      </AppLayout>
+    );
+    return render(() => (
       <Router>
-        <Route
+        <Route path="/settings/infrastructure" component={LayoutRoute} />
-          path="/settings/infrastructure"
+        <Route path="/proxmox/overview" component={LayoutRoute} />
-          component={() => (
+        <Route path="/docker/overview" component={LayoutRoute} />
-            <AppLayout
-              connectionStatus={() => ({
-                kind: 'connected',
-                label: 'Connected',
-                detail: 'Backend and live data stream are connected.',
-                tone: 'healthy',
-              })}
-              lastUpdateText={() => ''}
-              versionInfo={() =>
-                ({
-                  version: '6.0.0-rc.2',
-                  channel: 'rc',
-                  isDevelopment: false,
-                  isDocker: false,
-                }) as never
-              }
-              hasAuth={() => true}
-              needsAuth={() => false}
-              proxyAuthInfo={() => null}
-              handleLogout={() => {}}
-              state={() =>
-                ({
-                  activeAlerts: [{ id: 'alert-1', level: 'warning', acknowledged: false }],
-                  resources,
-                }) as unknown as State
-              }
-              tokenScopes={() => ['settings:read']}
-              organizations={() => []}
-              activeOrgID={() => 'default'}
-              orgsLoading={() => false}
-              showOrgSwitcher={() => false}
-              onSwitchOrg={() => {}}
-            >
-              <div>Infrastructure body</div>
-            </AppLayout>
-          )}
-        />
       </Router>
     ));
+  };
+
+  const getInfrastructureTab = (name: string) => {
+    const desktopNav = screen.getByRole('tablist', { name: 'Primary navigation' });
+    const infrastructureGroup = desktopNav.querySelector('[aria-label="Infrastructure"]');
+    expect(infrastructureGroup).toBeTruthy();
+    return within(infrastructureGroup as HTMLElement).getByRole('tab', { name });
+  };
+
+  const platformResources = () => [
+    makeResource({ id: 'pve-1', type: 'agent', platformType: 'proxmox-pve' }),
+    makeResource({ id: 'docker-1', type: 'docker-host', platformType: 'docker' }),
+  ];
 
   it('renders fresh utility icons for both desktop and mobile navigation trees', () => {
     const { container } = renderLayout();
@@ -193,6 +213,48 @@ describe('AppLayout navigation icons', () => {
     ).toBeTruthy();
   });
 
+  it('restores the previous Proxmox route state when returning from another platform tab', async () => {
+    renderLayout(platformResources(), '/proxmox/overview?status=running');
+
+    await fireEvent.click(getInfrastructureTab('Docker'));
+    await waitFor(() => {
+      expect(window.location.pathname).toBe('/docker/overview');
+      expect(window.location.search).toBe('');
+    });
+
+    await fireEvent.click(getInfrastructureTab('Proxmox'));
+    await waitFor(() => {
+      expect(window.location.pathname).toBe('/proxmox/overview');
+      expect(window.location.search).toBe('?status=running');
+    });
+  });
+
+  it('keeps remembered route state scoped to the platform tab that owns it', async () => {
+    renderLayout(platformResources(), '/docker/overview?host=docker-1');
+
+    await fireEvent.click(getInfrastructureTab('Proxmox'));
+    await waitFor(() => {
+      expect(window.location.pathname).toBe('/proxmox/overview');
+      expect(window.location.search).toBe('');
+    });
+
+    await fireEvent.click(getInfrastructureTab('Docker'));
+    await waitFor(() => {
+      expect(window.location.pathname).toBe('/docker/overview');
+      expect(window.location.search).toBe('?host=docker-1');
+    });
+  });
+
+  it('uses the canonical platform root route when there is no remembered route state', async () => {
+    renderLayout(platformResources(), '/settings/infrastructure');
+
+    await fireEvent.click(getInfrastructureTab('Proxmox'));
+    await waitFor(() => {
+      expect(window.location.pathname).toBe('/proxmox/overview');
+      expect(window.location.search).toBe('');
+    });
+  });
+
   it('keeps connected brand motion on the logo while the wordmark stays static', () => {
     const { container } = renderLayout();