fix: allow multiple editor instances to register inline shortcuts on document

Two bugs caused inline shortcuts to fail when multiple EditorJS instances
were on the same page:

1. Mismatch: shortcuts were registered on `document` but removed from
   `this.Editor.UI.nodes.redactor`, so they were never actually removed.

2. Because shortcuts accumulated on `document` forever, the second editor's
   attempt to register the same shortcuts threw an error (silently caught),
   meaning the second editor's inline shortcuts were never registered at all.

Fixes:
- Remove the throw in `Shortcuts.add()` to allow multiple editors to each
  register their own handler for the same shortcut on `document`. Each
  handler already guards via `if (!currentBlock) return`, so only the
  focused editor responds.
- Fix `close()` to call `Shortcuts.remove(document, shortcut)` matching
  where they were registered.
- Update type signatures from `Element` to `HTMLElement | Document` to
  match actual usage.

Agent-Logs-Url: https://github.com/codex-team/editor.js/sessions/6c11dfbe-e93a-4fd6-a88e-ef0409aa3d73

Co-authored-by: neSpecc <3684889+neSpecc@users.noreply.github.com>

Author: Copilot

src/components/modules/toolbar/inline.ts

@@ -110,7 +110,7 @@ export default class InlineToolbar extends Module<InlineToolbarNodes> {
       const shortcut = this.getToolShortcut(tool.name);
 
       if (shortcut !== undefined) {
-        Shortcuts.remove(this.Editor.UI.nodes.redactor, shortcut);
+        Shortcuts.remove(document, shortcut);
       }
 
       /**

src/components/utils/shortcuts.ts

@@ -41,24 +41,16 @@ class Shortcuts {
   /**
    * All registered shortcuts
    *
-   * @type {Map<Element, Shortcut[]>}
+   * @type {Map<HTMLElement | Document, Shortcut[]>}
    */
-  private registeredShortcuts: Map<Element, Shortcut[]> = new Map();
+  private registeredShortcuts: Map<HTMLElement | Document, Shortcut[]> = new Map();
 
   /**
    * Register shortcut
    *
    * @param shortcut - shortcut options
    */
   public add(shortcut: ShortcutData): void {
-    const foundShortcut = this.findShortcut(shortcut.on, shortcut.name);
-
-    if (foundShortcut) {
-      throw Error(
-        `Shortcut ${shortcut.name} is already registered for ${shortcut.on}. Please remove it before add a new handler.`
-      );
-    }
-
     const newShortcut = new Shortcut({
       name: shortcut.name,
       on: shortcut.on,
@@ -75,7 +67,7 @@ class Shortcuts {
    * @param element - Element shortcut is set for
    * @param name - shortcut name
    */
-  public remove(element: Element, name: string): void {
+  public remove(element: HTMLElement | Document, name: string): void {
     const shortcut = this.findShortcut(element, name);
 
     if (!shortcut) {
@@ -104,7 +96,7 @@ class Shortcuts {
    * @param shortcut - shortcut name
    * @returns {number} index - shortcut index if exist
    */
-  private findShortcut(element: Element, shortcut: string): Shortcut | void {
+  private findShortcut(element: HTMLElement | Document, shortcut: string): Shortcut | void {
     const shortcuts = this.registeredShortcuts.get(element) || [];
 
     return shortcuts.find(({ name }) => name === shortcut);