feat: MVP-5 P2 - Export/Import, Settings, Tests y Validaciones

- Ticket 10: Navegación completa de listas por teclado (↑↓ Enter E F P)
- Ticket 13: Historial de navegación contextual con recent-context-list
- Ticket 17: Exportación mejorada a Markdown con frontmatter
- Ticket 18: Exportación HTML simple y legible
- Ticket 19: Importador Markdown mejorado con frontmatter, tags, wiki links
- Ticket 20: Importador Obsidian-compatible (wiki links, #tags inline)
- Ticket 21: Centro de respaldo y portabilidad en Settings
- Ticket 22: Configuración visible de feature flags
- Ticket 24: Tests de command palette y captura externa
- Ticket 25: Harden de validaciones y límites (50MB backup, 10K notas, etc)

src/hooks/use-note-list-keyboard.ts

@@ -0,0 +1,87 @@
+import { useEffect, useCallback, useState } from 'react'
+import { useRouter } from 'next/navigation'
+import { Note } from '@/types/note'
+
+interface UseNoteListKeyboardOptions {
+  notes: Note[]
+  onEdit?: (noteId: string) => void
+  onFavorite?: (noteId: string) => void
+  onPin?: (noteId: string) => void
+}
+
+export function useNoteListKeyboard({
+  notes,
+  onEdit,
+  onFavorite,
+  onPin,
+}: UseNoteListKeyboardOptions) {
+  const [selectedIndex, setSelectedIndex] = useState(-1)
+  const router = useRouter()
+
+  // Reset selection when notes change
+  useEffect(() => {
+    setSelectedIndex(-1)
+  }, [notes.length])
+
+  const handleKeyDown = useCallback(
+    (e: KeyboardEvent) => {
+      // Ignore if in input/textarea/contenteditable
+      const target = e.target as HTMLElement
+      if (
+        target.tagName === 'INPUT' ||
+        target.tagName === 'TEXTAREA' ||
+        target.isContentEditable
+      ) {
+        return
+      }
+
+      switch (e.key) {
+        case 'ArrowDown':
+          e.preventDefault()
+          setSelectedIndex((prev) =>
+            prev < notes.length - 1 ? prev + 1 : notes.length - 1
+          )
+          break
+        case 'ArrowUp':
+          e.preventDefault()
+          setSelectedIndex((prev) => (prev > 0 ? prev - 1 : -1))
+          break
+        case 'Enter':
+          e.preventDefault()
+          if (selectedIndex >= 0 && notes[selectedIndex]) {
+            router.push(`/notes/${notes[selectedIndex].id}`)
+          }
+          break
+        case 'e':
+        case 'E':
+          if (selectedIndex >= 0 && notes[selectedIndex] && onEdit) {
+            e.preventDefault()
+            onEdit(notes[selectedIndex].id)
+          }
+          break
+        case 'f':
+        case 'F':
+          if (selectedIndex >= 0 && notes[selectedIndex] && onFavorite) {
+            e.preventDefault()
+            onFavorite(notes[selectedIndex].id)
+          }
+          break
+        case 'p':
+        case 'P':
+          if (selectedIndex >= 0 && notes[selectedIndex] && onPin) {
+            e.preventDefault()
+            onPin(notes[selectedIndex].id)
+          }
+          break
+      }
+    },
+    [notes, selectedIndex, router, onEdit, onFavorite, onPin]
+  )
+
+  useEffect(() => {
+    window.addEventListener('keydown', handleKeyDown)
+    return () => window.removeEventListener('keydown', handleKeyDown)
+  }, [handleKeyDown])
+
+  return { selectedIndex, setSelectedIndex }
+}