feat(nav): Design is primary navigation, not a utility icon

It sat in the right-hand icon cluster with Trash and Settings, filed as a
meta-surface. That was true when /design was a read-only gallery and false
since: a design system is a record you author, with its own table, inheritance,
sharing under the same ACL, and MCP tools. It is the content of the
applications being built, which is the same rule that puts Snippets and
Rulebooks in the bar.

The pill bar is absolutely centred, so a sixth link doesn't push the brand and
the utility cluster aside — it overlaps them. Added a 1150px breakpoint that
drops the wordmark (the logo says the same thing and is still the link home)
and tightens the link padding, rather than leaving Design out of the bar to
avoid the collision.

Mobile menu moves Design above the divider with the other content links, so
both layouts sort it the same way.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UaYUaouG9jjhATyuxCKrQs

frontend/src/components/AppHeader.vue

@@ -6,7 +6,7 @@ import { useShortcuts } from "@/composables/useShortcuts";
 import { useAuthStore } from "@/stores/auth";
 import AppLogo from "@/components/AppLogo.vue";
 import NotificationBell from "@/components/NotificationBell.vue";
-import { Sun, Moon, Palette, Settings, Trash2 } from "lucide-vue-next";
+import { Sun, Moon, Settings, Trash2 } from "lucide-vue-next";
 
 const { theme, toggleTheme } = useTheme();
 const { toggleShortcuts } = useShortcuts();
@@ -50,6 +50,12 @@ router.afterEach(() => {
           <router-link to="/projects" class="nav-link">Projects</router-link>
           <router-link to="/snippets" class="nav-link">Snippets</router-link>
           <router-link to="/rules" class="nav-link">Rulebooks</router-link>
+          <!-- A design system is a RECORD you author, not a setting. It sat in
+               the utility cluster with Trash and Settings while /design was a
+               read-only gallery, and stayed there after it became a record type
+               with its own table, sharing and MCP tools. Content, by the same
+               rule that puts Snippets and Rulebooks here. -->
+          <router-link to="/design-systems" class="nav-link">Design</router-link>
         </div>
       </div>
 
@@ -64,16 +70,6 @@ router.afterEach(() => {
           <Moon v-else :size="16" />
         </button>
 
-        <!-- Design. An icon rather than a sixth primary nav link: it's a
-             meta-surface like Trash and Settings, but hiding it entirely would
-             defeat the point of having somewhere the design system is visible.
-             Points at the RECORD, not the live-token view — the record is what
-             you work with; the live view is the check on it, and it's a tab
-             away. -->
-        <router-link to="/design-systems" class="btn-icon" aria-label="Design" title="Design">
-          <Palette :size="16" />
-        </router-link>
-
         <!-- Trash link -->
         <router-link to="/trash" class="btn-icon" aria-label="Trash" title="Trash">
           <Trash2 :size="16" />
@@ -106,9 +102,9 @@ router.afterEach(() => {
       <router-link to="/projects" class="nav-link">Projects</router-link>
       <router-link to="/snippets" class="nav-link">Snippets</router-link>
       <router-link to="/rules" class="nav-link">Rulebooks</router-link>
+      <router-link to="/design-systems" class="nav-link">Design</router-link>
       <router-link to="/shared" class="nav-link">Shared</router-link>
       <div class="mobile-divider"></div>
-      <router-link to="/design-systems" class="nav-link">Design</router-link>
       <router-link to="/trash" class="nav-link">Trash</router-link>
       <router-link to="/settings" class="nav-link">Settings</router-link>
       <div class="mobile-divider"></div>
@@ -346,6 +342,22 @@ router.afterEach(() => {
   margin-top: 0.25rem;
 }
 
+/* The pill bar is absolutely centred, so when the header runs out of room it
+   OVERLAPS the brand and the utility cluster rather than pushing them — nothing
+   wraps, it just collides. Six primary links reach that point sooner than five
+   did, so reclaim the width here instead of leaving one out of the bar.
+   The wordmark goes first: the logo beside it says the same thing and is still
+   the link home. */
+@media (max-width: 1150px) {
+  .brand-text {
+    display: none;
+  }
+  .nav-link {
+    padding: 0.3rem 0.5rem;
+    font-size: 0.78rem;
+  }
+}
+
 @media (max-width: 768px) {
   .nav-center {
     display: none;