Add spam review functionality to contact form and update translations

- Introduced a new spamReview property in the Form interface to handle manual review requests for messages flagged as spam.
- Updated the Form component to display a spam warning and a manual review form with dynamic labels and placeholders based on translations.
- Enhanced the Tailwind CSS styles for responsive subtitles across various components.
- Added corresponding translations for the spam review feature in English, Dutch, German, and French, ensuring consistency and clarity in messaging.
- Updated various components to integrate the new spamReview functionality, improving user experience and interaction.

src/pages/index.astro

@@ -163,5 +163,6 @@ const metadata = {
     }}
     description={t.homepage?.contact?.description ||
       "I'll respond to your message as soon as possible. You can also connect with me on LinkedIn or GitHub."}
+    spamReview={t.homepage?.spamReview}
   />
 </Layout>