feat(tv-input): gamepad->keyboard bridge daemon + controller-navigable modals

- archipelago-gamepad-keys: evdev->uinput daemon (pure python3 stdlib) that
  mirrors any attached controller as a virtual keyboard — D-pad/stick to
  arrows, A/B to Enter/Escape, X/Y to Space/f, shoulders to Tab/Shift+Tab.
  The browser sees real keys, so controllers work inside EVERY app iframe
  (IndeeHub, Jellyfin…) with zero per-app code. Ships via the ISO splice and
  bootstrap self-heal (kiosk nodes only), hotplug via 5s rescans.
  Implements docs/tv-input-iframe-apps.md.
- useControllerNav: an open [role=dialog][aria-modal] owns navigation —
  focus is pulled inside, arrows move spatially between its controls, Enter
  activates, Escape stays with the modal's own close handling. One standard
  mapping for every modal.

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

neode-ui/src/composables/useControllerNav.ts

@@ -105,6 +105,14 @@ function isInZone(el: HTMLElement | null, zone: 'sidebar' | 'main'): boolean {
   return !!el.closest(`[data-controller-zone="${zone}"]`)
 }
 
+/** Topmost open modal dialog, if any — it owns navigation while visible. */
+function getOpenModal(): HTMLElement | null {
+  const dialogs = Array.from(
+    document.querySelectorAll<HTMLElement>('[role="dialog"][aria-modal="true"]'),
+  ).filter(el => el.offsetParent !== null)
+  return dialogs[dialogs.length - 1] ?? null
+}
+
 function isInsideContainer(el: HTMLElement | null): boolean {
   if (!el) return false
   const container = el.closest('[data-controller-container]')
@@ -250,6 +258,42 @@ export function useControllerNav(containerRef?: { value: HTMLElement | null }) {
     const target = e.target as HTMLElement
     const activeEl = document.activeElement as HTMLElement
 
+    // ── MODAL SCOPE ──────────────────────────────────────────
+    // An open dialog owns navigation: focus is pulled inside, arrows move
+    // spatially between its controls, Enter activates. Escape stays with the
+    // modal's own close handling. Standard mapping, no per-modal code.
+    const modal = getOpenModal()
+    if (modal) {
+      if (e.key === 'Escape') return
+      const focusables = getFocusableElements(modal)
+      if (!focusables.length) return
+      if (!activeEl || !modal.contains(activeEl)) {
+        e.preventDefault()
+        const first = focusables[0]
+        if (first) focusEl(first)
+        return
+      }
+      if (target.tagName === 'INPUT' || target.tagName === 'TEXTAREA') {
+        // Typing keys stay with the field; Enter keeps the form-submit
+        // behavior below; only Up/Down leave the field spatially.
+        if (e.key === 'ArrowLeft' || e.key === 'ArrowRight' || e.key === 'Enter') return
+      } else if (e.key === 'Enter') {
+        e.preventDefault()
+        playNavSound('action')
+        activeEl.click()
+        return
+      }
+      e.preventDefault()
+      const dir =
+        e.key === 'ArrowDown' ? ('down' as const)
+        : e.key === 'ArrowUp' ? ('up' as const)
+        : e.key === 'ArrowLeft' ? ('left' as const)
+        : ('right' as const)
+      const nearest = findNearestInDirection(activeEl, focusables.filter(el => el !== activeEl), dir)
+      if (nearest) focusEl(nearest)
+      return
+    }
+
     // ── TEXT INPUT HANDLING ──────────────────────────────────
     if (target.tagName === 'INPUT' || target.tagName === 'TEXTAREA') {
       if (