feat(dashboard): Home view hides support panels for focused first impression

The Home hero was being crowded by the sidebar, inspector, and console
that surround it on every other view. Add a 'simple' grid layout that
collapses to just rail + topbar + main when view==='home', giving the
hero the full screen.

The moment a user clicks any non-Home rail icon (Scene, Apps, Inspector,
Witness, Ghost Murmur), the full power-user grid restores.

Co-Authored-By: claude-flow <ruv@ruv.net>

dashboard/src/components/nv-app.ts

@@ -60,6 +60,18 @@ export class NvApp extends LitElement {
       height: 100vh;
       width: 100vw;
     }
+    /* Home view simplifies: hides sidebar / inspector / console so the
+       hero gets the full screen. Power-user panels stay one rail click away. */
+    .app.simple {
+      grid-template-columns: 56px 1fr;
+      grid-template-rows: 48px 1fr;
+      grid-template-areas:
+        'rail topbar'
+        'rail main';
+    }
+    .app.simple nv-sidebar,
+    .app.simple nv-inspector,
+    .app.simple nv-console { display: none; }
     nv-rail { grid-area: rail; }
     nv-topbar { grid-area: topbar; }
     nv-sidebar { grid-area: sidebar; }
@@ -90,12 +102,13 @@ export class NvApp extends LitElement {
   `;
 
   override render() {
+    const isSimple = this.view === 'home';
     return html`
       <a class="skip-link" href="#main-content"
         @click=${(e: Event) => { e.preventDefault(); const sr = this.shadowRoot; sr?.querySelector<HTMLElement>('.main')?.focus(); }}>
         Skip to main content
       </a>
-      <div class="app">
+      <div class="app ${isSimple ? 'simple' : ''}">
         <nv-rail .view=${this.view} @navigate=${(e: CustomEvent<View>) => (this.view = e.detail)}></nv-rail>
         <nv-topbar></nv-topbar>
         <nv-sidebar></nv-sidebar>