feat: tighten mobile tabs and mission console theme

src/App.tsx

@@ -9,7 +9,6 @@ import type { AppState, Feature, FeatureColumn, ParkingLotItem, PulseEvent, Risk
 import { arrayToLines, formatDateTime, linesToArray, nowIso, slugify } from './utils/format'
 
 const TABS: Array<{ key: TabKey; label: string }> = [
-  { key: 'functionalities', label: 'Functionalities' },
   { key: 'feature-plan', label: 'Feature Plan' },
   { key: 'parking-lot', label: 'Parking Lot' },
   { key: 'pulse-log', label: 'Pulse Log' },
@@ -66,7 +65,7 @@ const downloadText = (filename: string, text: string, contentType = 'text/plain;
 
 function App() {
   const [appState, setAppState] = useState<AppState>(() => loadAppState())
-  const [activeTab, setActiveTab] = useState<TabKey>('functionalities')
+  const [activeTab, setActiveTab] = useState<TabKey>('feature-plan')
   const [statusMessage, setStatusMessage] = useState('Seeded with BuildPulse so you can dogfood it immediately.')
   const [selectedFeatureId, setSelectedFeatureId] = useState<string | null>(null)
   const [selectedParkingId, setSelectedParkingId] = useState<string | null>(null)
@@ -786,11 +785,13 @@ function App() {
         </div>
       </section>
 
-      <nav className="tab-bar" aria-label="Main views">
+      <nav className="tab-bar" aria-label="BuildPulse v0.1 views" role="tablist">
         {TABS.map((tab) => (
           <button
             key={tab.key}
             type="button"
+            role="tab"
+            aria-selected={tab.key === activeTab}
             className={tab.key === activeTab ? 'tab active' : 'tab'}
             onClick={() => setActiveTab(tab.key)}
           >