feat(ui): per-app display-mode defaults (IndeeHub fullscreen) + gamepad plays media + node list scales

- Per-app default display mode: explicit user pick (remembered per app) ->
  app default -> last global -> panel; IndeeHub defaults to fullscreen.
- data-controller-primary: a media file card's gamepad-select clicks the
  card (audio -> bottom-bar player, video -> lightbox) instead of the
  card's download link.
- Discovered-nodes list scales with the viewport (max(14rem,45vh)) instead
  of cramming a long list into a fixed 224px box.

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

neode-ui/src/views/AppSession.vue

@@ -103,7 +103,7 @@ import AppSessionFrame from './appSession/AppSessionFrame.vue'
 import MobileGamepad from './appSession/MobileGamepad.vue'
 import {
   type DisplayMode, DISPLAY_MODE_KEY, NEW_TAB_APPS, IFRAME_BLOCKED_APPS,
-  resolveAppUrl, resolveAppTitle,
+  initialDisplayMode, resolveAppUrl, resolveAppTitle,
 } from './appSession/appSessionConfig'
 import { launchBlockedReason, resolveAppIcon } from './apps/appsConfig'
 import { useAppIdentity } from './appSession/useAppIdentity'
@@ -142,11 +142,6 @@ let loadTimeoutId: ReturnType<typeof setTimeout> | null = null
 let autoRetryId: ReturnType<typeof setTimeout> | null = null
 let iframeCheckId: ReturnType<typeof setTimeout> | null = null
 
-// Display mode -- persisted in localStorage
-const displayMode = ref<DisplayMode>(
-  (localStorage.getItem(DISPLAY_MODE_KEY) as DisplayMode) || 'panel'
-)
-
 const appId = computed(() => {
   const id = props.appIdProp || (route.params.appId as string)
   if (typeof id !== 'string' || !/^[a-z0-9][a-z0-9._-]*$/.test(id) || id.length > 64) {
@@ -156,6 +151,9 @@ const appId = computed(() => {
   return id
 })
 
+// Display mode -- per-app user choice → per-app default → last global → panel
+const displayMode = ref<DisplayMode>(initialDisplayMode(appId.value))
+
 const appTitle = computed(() => resolveAppTitle(appId.value))
 const packageEntry = computed(() => store.data?.['package-data']?.[appId.value] || null)
 const appIcon = computed(() =>
@@ -231,6 +229,8 @@ function setMode(mode: DisplayMode) {
   }
   displayMode.value = mode
   localStorage.setItem(DISPLAY_MODE_KEY, mode)
+  // Remember the explicit pick for this app so it wins over the app default.
+  if (appId.value) localStorage.setItem(`${DISPLAY_MODE_KEY}:${appId.value}`, mode)
 
   // Route-based sessions (deep links) hand off to the store-driven session so
   // the app keeps floating above the dashboard instead of owning the route.
@@ -367,6 +367,7 @@ function onFullscreenChange() {
   if (!document.fullscreenElement && displayMode.value === 'fullscreen') {
     displayMode.value = 'overlay'
     localStorage.setItem(DISPLAY_MODE_KEY, 'overlay')
+    if (appId.value) localStorage.setItem(`${DISPLAY_MODE_KEY}:${appId.value}`, 'overlay')
   }
 }