feat: add v-shortcut directive for keyboard shortcuts (#942)

Co-authored-by: kolaente <k@knt.li>
Reviewed-on: https://kolaente.dev/vikunja/frontend/pulls/942
Reviewed-by: dpschen <dpschen@noreply.kolaente.de>
Co-authored-by: konrad <k@knt.li>
Co-committed-by: konrad <k@knt.li>

src/components/home/contentAuth.vue

@@ -31,8 +31,7 @@
 				<a
 					class="keyboard-shortcuts-button"
 					@click="showKeyboardShortcuts()"
-					@shortkey="showKeyboardShortcuts()"
-					v-shortkey="['?']"
+					v-shortcut="'?'"
 				>
 					<icon icon="keyboard"/>
 				</a>