feat(ui): route persistence, sidebar active fix, header spacing

- Persist last visited path via Zustand persist, restore on login/root
- Sidebar: exact match for active state (issue detail no longer highlights Issues)
- Sidebar header: increase vertical padding
- Inbox unread count: simplified to text-xs

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/web/app/(auth)/login/page.tsx

@@ -4,6 +4,7 @@ import { Suspense, useState } from "react";
 import { useSearchParams, useRouter } from "next/navigation";
 import { useAuthStore } from "@/features/auth";
 import { useWorkspaceStore } from "@/features/workspace";
+import { useNavigationStore } from "@/features/navigation";
 import { api } from "@/shared/api";
 import {
   Card,
@@ -40,7 +41,8 @@ function LoginPageContent() {
       await login(email, name || undefined);
       const wsList = await api.listWorkspaces();
       await hydrateWorkspace(wsList);
-      router.push(searchParams.get("next") || "/issues");
+      const fallback = useNavigationStore.getState().lastPath;
+      router.push(searchParams.get("next") || fallback);
     } catch (err) {
       setError("Login failed. Make sure the server is running.");
       setSubmitting(false);

apps/web/app/(dashboard)/_components/app-sidebar.tsx

@@ -73,7 +73,7 @@ export function AppSidebar() {
   return (
       <Sidebar variant="inset">
         {/* Workspace Switcher */}
-        <SidebarHeader>
+        <SidebarHeader className="py-3">
           <div className="flex items-center gap-4">
             <SidebarMenu className="min-w-0 flex-1">
               <SidebarMenuItem>
@@ -181,9 +181,7 @@ export function AppSidebar() {
             <SidebarGroupContent>
               <SidebarMenu className="gap-0.5">
                 {navItems.map((item) => {
-                  const isActive =
-                    pathname === item.href ||
-                    pathname.startsWith(item.href + "/");
+                  const isActive = pathname === item.href;
                   return (
                     <SidebarMenuItem key={item.href}>
                       <SidebarMenuButton
@@ -194,7 +192,7 @@ export function AppSidebar() {
                         <item.icon />
                         <span>{item.label}</span>
                         {item.label === "Inbox" && unreadCount > 0 && (
-                          <span className="ml-auto rounded-full bg-primary px-1.5 py-0.5 text-[10px] font-medium text-primary-foreground">
+                          <span className="ml-auto text-xs">
                             {unreadCount > 99 ? "99+" : unreadCount}
                           </span>
                         )}
@@ -213,7 +211,7 @@ export function AppSidebar() {
             <SidebarMenu>
               <SidebarMenuItem>
                 <SidebarMenuButton size="sm">
-                  <div className="flex h-5 w-5 shrink-0 items-center justify-center rounded-full bg-muted text-[9px] font-medium">
+                  <div className="flex h-5 w-5 shrink-0 items-center justify-center rounded-full bg-muted text-xs leading-none font-medium">
                     {user.name
                       .split(" ")
                       .map((w) => w[0])

apps/web/app/(dashboard)/layout.tsx

@@ -1,8 +1,9 @@
 "use client";
 
 import { useEffect } from "react";
-import { useRouter } from "next/navigation";
+import { useRouter, usePathname } from "next/navigation";
 import { MulticaIcon } from "@/components/multica-icon";
+import { useNavigationStore } from "@/features/navigation";
 import { SidebarProvider, SidebarInset } from "@/components/ui/sidebar";
 import { useAuthStore } from "@/features/auth";
 import { useWorkspaceStore } from "@/features/workspace";
@@ -14,6 +15,7 @@ export default function DashboardLayout({
   children: React.ReactNode;
 }) {
   const router = useRouter();
+  const pathname = usePathname();
   const user = useAuthStore((s) => s.user);
   const isLoading = useAuthStore((s) => s.isLoading);
   const workspace = useWorkspaceStore((s) => s.workspace);
@@ -24,6 +26,10 @@ export default function DashboardLayout({
     }
   }, [user, isLoading, router]);
 
+  useEffect(() => {
+    useNavigationStore.getState().onPathChange(pathname);
+  }, [pathname]);
+
   if (isLoading) {
     return (
       <div className="flex h-screen items-center justify-center">
@@ -35,9 +41,9 @@ export default function DashboardLayout({
   if (!user || !workspace) return null;
 
   return (
-    <SidebarProvider>
+    <SidebarProvider className="max-h-svh">
       <AppSidebar />
-      <SidebarInset>{children}</SidebarInset>
+      <SidebarInset className="overflow-hidden">{children}</SidebarInset>
     </SidebarProvider>
   );
 }

apps/web/app/page.tsx

@@ -1,5 +1,21 @@
-import { redirect } from "next/navigation";
+"use client";
+
+import { useEffect } from "react";
+import { useRouter } from "next/navigation";
+import { useNavigationStore } from "@/features/navigation";
+import { MulticaIcon } from "@/components/multica-icon";
 
 export default function Home() {
-  redirect("/issues");
+  const router = useRouter();
+
+  useEffect(() => {
+    const lastPath = useNavigationStore.getState().lastPath;
+    router.replace(lastPath);
+  }, [router]);
+
+  return (
+    <div className="flex h-screen items-center justify-center">
+      <MulticaIcon className="size-6" />
+    </div>
+  );
 }

apps/web/features/navigation/index.ts

@@ -0,0 +1 @@
+export { useNavigationStore } from "./store";

apps/web/features/navigation/store.ts

@@ -0,0 +1,29 @@
+"use client";
+
+import { create } from "zustand";
+import { persist } from "zustand/middleware";
+
+const EXCLUDED_PREFIXES = ["/login", "/pair/"];
+
+interface NavigationState {
+  lastPath: string;
+  onPathChange: (path: string) => void;
+}
+
+export const useNavigationStore = create<NavigationState>()(
+  persist(
+    (set) => ({
+      lastPath: "/issues",
+
+      onPathChange: (path: string) => {
+        if (!EXCLUDED_PREFIXES.some((prefix) => path.startsWith(prefix))) {
+          set({ lastPath: path });
+        }
+      },
+    }),
+    {
+      name: "multica_navigation",
+      partialize: (state) => ({ lastPath: state.lastPath }),
+    }
+  )
+);