feat: improve move dialog with folder navigation

- Remove 'Root' option from move dialog (users move within their home folder)
- Show children of current folder instead of flat folder list
- Add breadcrumb navigation for folder browsing
- Add 'go to parent' navigation option
- Add 'select this folder' option to choose current location
- Add CSS styles for new navigation elements
- Add dark mode support for move dialog
- Add i18n translations for new strings (en, es)

static/locales/en.json

@@ -202,6 +202,9 @@
     "move_file": "Move file",
     "move_folder": "Move folder",
     "select_destination": "Select destination folder:",
+    "select_this_folder": "Select this folder",
+    "go_to_parent": ".. (parent folder)",
+    "no_subfolders": "No subfolders",
     "root": "Root",
     "delete_confirmation": "Are you sure you want to delete",
     "and_contents": "and all its contents",

static/locales/es.json

@@ -202,6 +202,9 @@
     "move_file": "Mover archivo",
     "move_folder": "Mover carpeta",
     "select_destination": "Selecciona la carpeta destino:",
+    "select_this_folder": "Seleccionar esta carpeta",
+    "go_to_parent": ".. (carpeta superior)",
+    "no_subfolders": "Sin subcarpetas",
     "root": "Raíz",
     "delete_confirmation": "¿Estás seguro de que quieres eliminar",
     "and_contents": "y todo su contenido",