Export the editing API of json_view from the C++20 module (#6090)

Signed-off-by: Niels Lohmann <mail@nlohmann.me>

docs/mkdocs/docs/features/modules.md

@@ -36,15 +36,21 @@ Only the following symbols are exported from `nlohmann.json`:
 - `nlohmann::basic_json`
 - `nlohmann::basic_json_document`
 - `nlohmann::basic_json_view`
+- `nlohmann::is_json_view`
 - `nlohmann::json`
 - `nlohmann::json_document`
+- `nlohmann::json_editable_document`
+- `nlohmann::json_editable_view`
 - `nlohmann::json_pointer`
 - `nlohmann::json_view`
 - `nlohmann::ordered_json`
 - `nlohmann::ordered_json_document`
+- `nlohmann::ordered_json_editable_document`
+- `nlohmann::ordered_json_editable_view`
 - `nlohmann::ordered_json_view`
 - `nlohmann::ordered_map`
 - `nlohmann::to_string`
+- `nlohmann::view_mode`
 - `nlohmann::literals::json_literals::operator""_json`
 - `nlohmann::literals::json_literals::operator""_json_pointer`
 
@@ -56,6 +62,7 @@ Additionally, the following `nlohmann::detail` symbols are exported, solely to w
 and should not be used directly:
 
 - `nlohmann::detail::json_sax_dom_callback_parser`
+- `nlohmann::detail::json_sax_dom_parser`
 - `nlohmann::detail::unknown_size`
 
 ## Known issues