Support for multiple hotkeys/sequences registration at once

[niusia-ua]

Calling useHotkey/useHotkeySequence is too verbose. It would be nice to be able to register all the necessary hotkeys at once:

useHotkeys(
  {
    // Simple registration.
    "Ctrl+Z": () => { ... },

    // With options override.
    "Ctrl+Y": {
      callback: () => { ... },
      options: { ... },
    },
  },
  { /* common options for this registration */ },
 );

This will be extremely helpful when working with menus and their items, similar to Nuxt UI:

<script setup lang="ts">
import type { DropdownMenuItem } from '@nuxt/ui'

const items: DropdownMenuItem[] = [{
  label: 'Invite users',
  icon: 'i-lucide-user-plus',
  children: [{
    label: 'Invite by email',
    icon: 'i-lucide-send-horizontal',
    kbds: ['meta', 'e'],
    onSelect() {
      console.log('Invite by email clicked')
    }
  }, {
    label: 'Invite by link',
    icon: 'i-lucide-link',
    kbds: ['meta', 'i'],
    onSelect() {
      console.log('Invite by link clicked')
    }
  }]
}, {
  label: 'New team',
  icon: 'i-lucide-plus',
  kbds: ['meta', 'n'],
  onSelect() {
    console.log('New team clicked')
  }
}]

defineShortcuts(extractShortcuts(items))
</script>

The Nuxt UI is just an example of the API. They have their custom shortcuts system.

However, there is an issue with hotkey sequences (["G", "G"]) and object hotkeys ({ key: 'S', mod: true }), as objects can't have other objects or arrays as their keys. To support such keys, we may need to accept Map instead of an object. Or we can accept only string hotkeys for multi-registration: Ctrl+Z for hotkeys and G-G or G-Ctrl+Z for hotkey sequences.