feat: Update sidebar controls and navigation for improved UX and accessibility

src/app/globals.css

@@ -978,7 +978,44 @@ body {
   transition: width 0.5s ease;
 }
 
-/* Sidebar nav items */
+/* Sidebar controls and navigation */
+.sidebar-trigger {
+  width: 32px;
+  height: 32px;
+  flex: 0 0 32px;
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  padding: 0;
+  border: 1px solid transparent;
+  border-radius: 7px;
+  background: transparent;
+  color: var(--text-secondary);
+  cursor: pointer;
+  transition:
+    background 0.15s ease,
+    border-color 0.15s ease,
+    color 0.15s ease;
+}
+
+.sidebar-trigger:hover {
+  background: var(--bg-input);
+  border-color: var(--border);
+  color: var(--text-primary);
+}
+
+.sidebar-trigger:focus-visible {
+  outline: 2px solid var(--accent-blue);
+  outline-offset: 2px;
+}
+
+.topbar-section-divider {
+  width: 1px;
+  height: 20px;
+  flex: 0 0 1px;
+  background: var(--border);
+}
+
 .nav-item {
   display: flex;
   align-items: center;

src/components/DashboardLayout.tsx

@@ -74,7 +74,6 @@ export default function DashboardLayout({
       {/* Sidebar — handles its own backdrop overlay for mobile */}
       <Sidebar
         collapsed={collapsed}
-        onToggle={() => setCollapsed(!collapsed)}
         isMobile={isMobile}
         mobileOpen={mobileOpen}
         onMobileClose={() => setMobileOpen(false)}
@@ -96,6 +95,10 @@ export default function DashboardLayout({
           onMobileMenuToggle={
             isMobile ? () => setMobileOpen(!mobileOpen) : undefined
           }
+          onSidebarToggle={
+            isMobile ? undefined : () => setCollapsed((value) => !value)
+          }
+          sidebarCollapsed={collapsed}
         />
         <main
           className="p-4 md:p-6"

src/components/Sidebar.tsx

@@ -10,13 +10,11 @@ import OrganizationSwitcher from "@/components/OrganizationSwitcher";
 import { navigation } from "@/lib/navigation";
 import { addPreferencesListener, getStoredPanelName } from "@/lib/preferences";
 import { formatRoleLabel, hasMinimumRole } from "@/lib/permissions";
-import { LogOut, ChevronsUpDown, ChevronLeft, ChevronRight, X, Crown } from "lucide-react";
+import { LogOut, ChevronsUpDown, X, Crown } from "lucide-react";
 
 interface SidebarProps {
   /** Desktop: whether sidebar is in collapsed (icon-only) state */
   collapsed: boolean;
-  /** Desktop: called when user clicks the collapse toggle */
-  onToggle: () => void;
   /** Mobile: whether screen is narrow */
   isMobile: boolean;
   /** Mobile: whether the drawer is open */
@@ -27,7 +25,6 @@ interface SidebarProps {
 
 export default function Sidebar({
   collapsed,
-  onToggle,
   isMobile,
   mobileOpen,
   onMobileClose,
@@ -124,6 +121,7 @@ export default function Sidebar({
 
   const sidebar = (
     <aside
+      id="dashboard-sidebar"
       style={{
         position: "relative",
         width: isMobile ? "240px" : isCollapsed ? "60px" : "220px",
@@ -136,7 +134,7 @@ export default function Sidebar({
         flexShrink: 0,
       }}
     >
-      {/* ── Logo + collapse/close button ──────────────────────── */}
+      {/* ── Logo + mobile close button ────────────────────────── */}
       <div
         style={{
           padding: isCollapsed ? "0 12px" : "0 12px 0 16px",
@@ -195,57 +193,18 @@ export default function Sidebar({
           </div>
         )}
 
-        {/* Collapse toggle (desktop) or close button (mobile) */}
-        <button
-          onClick={isMobile ? onMobileClose : onToggle}
-          title={
-            isMobile
-              ? "Close menu"
-              : isCollapsed
-                ? "Expand sidebar"
-                : "Collapse sidebar"
-          }
-          style={{
-            position: isMobile ? "static" : "absolute",
-            right: isMobile ? undefined : -14,
-            top: isMobile ? undefined : 18,
-            zIndex: 50,
-            flexShrink: 0,
-            width: 28,
-            height: 28,
-            borderRadius: "50%",
-            background: "var(--bg-sidebar)",
-            border: "1px solid var(--border)",
-            display: "flex",
-            alignItems: "center",
-            justifyContent: "center",
-            cursor: "pointer",
-            color: "var(--text-muted)",
-            transition: "background 0.15s, color 0.15s, border-color 0.15s",
-            marginLeft: isMobile ? "auto" : undefined,
-            boxShadow: isMobile ? "none" : "0 2px 8px rgba(0,0,0,0.2)",
-          }}
-          onMouseEnter={(e) => {
-            const btn = e.currentTarget;
-            btn.style.background = "rgba(59,130,246,0.12)";
-            btn.style.borderColor = "rgba(59,130,246,0.4)";
-            btn.style.color = "#3b82f6";
-          }}
-          onMouseLeave={(e) => {
-            const btn = e.currentTarget;
-            btn.style.background = "var(--bg-sidebar)";
-            btn.style.borderColor = "var(--border)";
-            btn.style.color = "var(--text-muted)";
-          }}
-        >
-          {isMobile ? (
+        {isMobile && (
+          <button
+            type="button"
+            onClick={onMobileClose}
+            title="Close menu"
+            aria-label="Close menu"
+            className="sidebar-trigger"
+            style={{ marginLeft: "auto" }}
+          >
             <X size={13} />
-          ) : isCollapsed ? (
-            <ChevronRight size={13} />
-          ) : (
-            <ChevronLeft size={13} />
-          )}
-        </button>
+          </button>
+        )}
       </div>
 
       <OrganizationSwitcher

src/components/Topbar.tsx

@@ -19,6 +19,7 @@ import {
   LoaderCircle,
   Menu,
   Moon,
+  PanelLeft,
   RefreshCw,
   Search,
   SunMedium,
@@ -56,12 +57,16 @@ interface TopbarProps {
   title: string;
   subtitle?: string;
   onMobileMenuToggle?: () => void;
+  onSidebarToggle?: () => void;
+  sidebarCollapsed?: boolean;
 }
 
 export default function Topbar({
   title,
   subtitle,
   onMobileMenuToggle,
+  onSidebarToggle,
+  sidebarCollapsed = false,
 }: TopbarProps) {
   const currentUser = useCurrentUser();
   const pathname = usePathname();
@@ -424,9 +429,9 @@ export default function Topbar({
       }}
       className="md:px-6 md:gap-4"
     >
-      {/* Left: hamburger (mobile) + title */}
+      {/* Left: navigation control + title */}
       <div
-        style={{ display: "flex", alignItems: "center", gap: 8, minWidth: 0 }}
+        style={{ display: "flex", alignItems: "center", gap: 10, minWidth: 0 }}
       >
         {onMobileMenuToggle && (
           <button
@@ -447,6 +452,26 @@ export default function Topbar({
             <Menu size={20} />
           </button>
         )}
+        {onSidebarToggle && (
+          <>
+            <button
+              type="button"
+              onClick={onSidebarToggle}
+              className="sidebar-trigger"
+              aria-controls="dashboard-sidebar"
+              aria-expanded={!sidebarCollapsed}
+              aria-label={
+                sidebarCollapsed ? "Expand sidebar" : "Collapse sidebar"
+              }
+              title={
+                sidebarCollapsed ? "Expand sidebar" : "Collapse sidebar"
+              }
+            >
+              <PanelLeft size={18} strokeWidth={1.8} />
+            </button>
+            <span className="topbar-section-divider" aria-hidden="true" />
+          </>
+        )}
         <div style={{ minWidth: 0, overflow: "hidden", whiteSpace: "nowrap" }}>
           <h1
             style={{