fix(intro): audible entrance oomph, splash off deep routes, finale on intro shortcuts — with e2e cinematic suite

Three first-visit-experience bugs, all caught by the new e2e suite
(e2e/intro-experience.spec.ts — 5 tests against the demo stack on real
Chrome, instrumenting HTMLMediaElement/WebAudio/MutationObserver since
headless can't hear or see the cinematic):

- playDashboardLoadOomph was always silent: the login→dashboard route
  change closes the AudioContext (stopAllAudio), and the oomph only
  fetched the dead context. It now recreates one, riding the login
  click's sticky user activation.
- A direct /login load in the demo hijacked into the splash: App.vue
  read route.path before the router resolved the initial navigation, so
  every deep-route boot looked like a root boot. The splash decision now
  reads window.location.pathname.
- Replayed intros ran mute (enableCinematicSounds override) and the
  intro's shortcut exits skipped the dashboard finale (flag now armed on
  both demo and login exits).

Verified: 5/5 e2e, 673/673 unit, vue-tsc clean.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

neode-ui/src/views/OnboardingIntro.vue

@@ -69,12 +69,22 @@ onMounted(() => {
   }, 2100)
 })
 
+/** Any exit from the intro INTO login is the end of the cinematic — hand the
+ *  login the one-shot finale flag so the dashboard plays its full first-entry
+ *  reveal (zoom + oomph). OnboardingDone sets the same flag at the end of the
+ *  full wizard; these are the shortcut exits that used to skip it (which is
+ *  why the demo never got the big entrance). */
+function armOnboardingFinale() {
+  try { sessionStorage.setItem('archy_onboarding_finale', '1') } catch { /* ignore */ }
+}
+
 function goToOptions() {
   playNavSound('action')
   // Demo: skip the onboarding wizard (seed/identity setup) entirely — go straight
   // to login, which is prefilled with the demo password.
   if (isDemo) {
     localStorage.setItem('neode_onboarding_complete', '1')
+    armOnboardingFinale()
     router.push('/login').catch(() => {})
     return
   }
@@ -89,6 +99,7 @@ function goToRestore() {
 function goToLogin() {
   playNavSound('action')
   localStorage.setItem('neode_onboarding_complete', '1')
+  armOnboardingFinale()
   router.push('/login').catch(() => {})
 }
 </script>