Fix Shift+Insert, Ctrl+Insert, and Ctrl+Delete shortcuts

Fixes #338

These function calls used the wrong names since they were introduced
in 567fd6f1ad

Author: 1j01

src/app.js

@@ -1,15 +1,15 @@
 // @ts-check
 // eslint-disable-next-line no-unused-vars
 /* global airbrush_size:writable, brush_shape:writable, brush_size:writable, button:writable, ctrl:writable, eraser_size:writable, fill_color:writable, fill_color_k:writable, history_node_to_cancel_to:writable, MenuBar:writable, my_canvas_height:writable, my_canvas_width:writable, palette:writable, pencil_size:writable, pointer:writable, pointer_active:writable, pointer_buttons:writable, pointer_over_canvas:writable, pointer_previous:writable, pointer_start:writable, pointer_type:writable, pointers:writable, reverse:writable, shift:writable, stroke_color:writable, stroke_color_k:writable, stroke_size:writable, update_helper_layer_on_pointermove_active:writable */
-/* global copy, current_history_node, cut, default_airbrush_size, default_brush_shape, default_brush_size, default_canvas_height, default_canvas_width, default_eraser_size, default_magnification, default_pencil_size, default_stroke_size, enable_fs_access_api, file_name, get_direction, localize, magnification, main_canvas, main_ctx, remove_hotkey, return_to_tools, selected_colors, selected_tool, selected_tools, selection, showSaveFilePicker, systemHooks, textbox, transparency */
+/* global current_history_node, default_airbrush_size, default_brush_shape, default_brush_size, default_canvas_height, default_canvas_width, default_eraser_size, default_magnification, default_pencil_size, default_stroke_size, enable_fs_access_api, file_name, get_direction, localize, magnification, main_canvas, main_ctx, remove_hotkey, return_to_tools, selected_colors, selected_tool, selected_tools, selection, showSaveFilePicker, systemHooks, textbox, transparency */
 
 import { $ColorBox } from "./$ColorBox.js";
 import { $ToolBox } from "./$ToolBox.js";
 import { Handles } from "./Handles.js";
 // import { get_direction, localize, remove_hotkey } from "./app-localization.js";
 import { default_palette, get_winter_palette } from "./color-data.js";
 import { image_formats } from "./file-format-data.js";
-import { $this_version_news, cancel, change_url_param, clear, confirm_overwrite_capability, delete_selection, deselect, edit_copy, edit_cut, file_new, file_open, file_save, file_save_as, get_tool_by_id, get_uris, image_attributes, image_flip_and_rotate, image_invert_colors, image_stretch_and_skew, load_image_from_uri, make_or_update_undoable, open_from_file, paste, paste_image_from_file, redo, render_history_as_gif, reset_canvas_and_history, reset_file, reset_selected_colors, resize_canvas_and_save_dimensions, resize_canvas_without_saving_dimensions, save_as_prompt, select_all, select_tool, select_tools, set_magnification, show_document_history, show_error_message, show_news, show_resource_load_error_message, toggle_grid, undo, update_canvas_rect, update_disable_aa, update_helper_layer, update_magnified_canvas_size, view_bitmap, write_image_file } from "./functions.js";
+import { $this_version_news, cancel, change_url_param, clear, confirm_overwrite_capability, delete_selection, deselect, edit_copy, edit_cut, edit_paste, file_new, file_open, file_save, file_save_as, get_tool_by_id, get_uris, image_attributes, image_flip_and_rotate, image_invert_colors, image_stretch_and_skew, load_image_from_uri, make_or_update_undoable, open_from_file, paste, paste_image_from_file, redo, render_history_as_gif, reset_canvas_and_history, reset_file, reset_selected_colors, resize_canvas_and_save_dimensions, resize_canvas_without_saving_dimensions, save_as_prompt, select_all, select_tool, select_tools, set_magnification, show_document_history, show_error_message, show_news, show_resource_load_error_message, toggle_grid, undo, update_canvas_rect, update_disable_aa, update_helper_layer, update_magnified_canvas_size, view_bitmap, write_image_file } from "./functions.js";
 import { show_help } from "./help.js";
 import { $G, E, TAU, get_file_extension, get_help_folder_icon, is_discord_embed, make_canvas, to_canvas_coords } from "./helpers.js";
 import { init_webgl_stuff, rotate } from "./image-manipulation.js";
@@ -961,7 +961,7 @@ $G.on("keydown", e => {
 		// shift+delete: cut
 		// delete/backspace: delete selection
 		if (e.key === "Delete" && e.shiftKey) {
-			cut();
+			edit_cut();
 		} else if (e.key === "Backspace" && e.altKey) {
 			undo();
 		} else {
@@ -972,10 +972,10 @@ $G.on("keydown", e => {
 		// ctrl+insert: copy
 		// shift+insert: paste
 		if (e.ctrlKey) {
-			copy();
+			edit_copy();
 			e.preventDefault();
 		} else if (e.shiftKey) {
-			paste();
+			edit_paste();
 			e.preventDefault();
 		}
 	} else if (