Add: Introduce a useTranslation hook

Provide a possibility to migrate our translation mechanism to react-i18n
by introducing a similar useTranslation hook.

When we started developing GSA hooks didn't exist and react-i18n
including its translation mechanisms were not easy to use. Therefore
I've implemented our own abstraction on top of i18next directly. With
react hooks react-i18n become much easier to use and we should migrate
to it at the end.

To allow for an easy migration introduce a similar useTranslation hook
as react-i18n that wraps our current translation code.

src/web/hooks/__tests__/useTranslation.js

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+/* SPDX-FileCopyrightText: 2024 Greenbone AG
+ *
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+import {fireEvent, rendererWith, screen} from 'web/utils/testing';
+
+import useTranslation from '../useTranslation';
+
+const TestComponent = () => {
+  const [_, i18n_1, ready_1] = useTranslation();
+  const {t, i18n, ready} = useTranslation();
+  return (
+    <div>
+      <div data-testid="t1">{_('First Translation')}</div>
+      <div data-testid="t2">{t('Second Translation')}</div>
+      <div data-testid="r1">{ready_1 ? 'is ready' : 'not ready'}</div>
+      <div data-testid="r2">{ready ? 'is ready' : 'not ready'}</div>
+      <button
+        data-testid="changeLocale1"
+        onClick={() => i18n.changeLanguage('en')}
+      />
+      <button
+        data-testid="changeLocale2"
+        onClick={() => i18n_1.changeLanguage('en')}
+      />
+    </div>
+  );
+};
+
+describe('useTranslation tests', () => {
+  test('should render the translations', async () => {
+    const {render} = rendererWith();
+
+    render(<TestComponent />);
+
+    const t1 = await screen.getByTestId('t1');
+    expect(t1).toHaveTextContent('First Translation');
+    const t2 = await screen.getByTestId('t2');
+    expect(t2).toHaveTextContent('Second Translation');
+    const r1 = await screen.getByTestId('r1');
+    expect(r1).toHaveTextContent('is ready');
+    const r2 = await screen.getByTestId('r2');
+    expect(r2).toHaveTextContent('is ready');
+    const b1 = await screen.getByTestId('changeLocale1');
+    await fireEvent.click(b1);
+    const b2 = await screen.getByTestId('changeLocale2');
+    await fireEvent.click(b2);
+  });
+});

src/web/hooks/useTranslation.js

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+/* SPDX-FileCopyrightText: 2024 Greenbone AG
+ *
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+import _ from 'gmp/locale';
+import i18next from 'i18next';
+
+/**
+ * Hook to get the translation function, an i18next instance and a boolean
+ * indicating if the translations are ready. Currently, the ready status is
+ * always true.
+ *
+ * The return value can be used as in array or object.
+ *
+ * @example
+ *
+ * const [_, i18n, ready] = useTranslation();
+ *
+ * or
+ *
+ * const {t, i18n, ready} = useTranslation();
+ *
+ * @returns Array|Object with the translation function, i18next instance and ready status
+ */
+const useTranslation = () => {
+  // provide same interface as useTranslation from i18next
+  // this will allow to use react-i18next in future if required
+  const ret = [_, i18next, true];
+  ret.t = _;
+  ret.i18n = i18next;
+  ret.ready = true;
+  return ret;
+};
+
+export default useTranslation;