feat: add spam warning to contact page

OliverBooth/Pages/Contact/Index.cshtml

@@ -10,6 +10,31 @@
     can.
 </p>
 
+<div class="alert alert-warning">
+    <p class="lead"><i class="fa-solid fa-triangle-exclamation"></i> Spam warning</p>
+    <p>
+        In the short time that this site has been live, I have received a considerable amount of spam that I suspect is
+        automated. As such, I added background reCaptcha validation to this form to minimise the amount of
+        bot-written junk I receive. However, some spam still gets through - that means there are humans reading this.
+    </p>
+    <p>
+        I am politely asking that you respect my inbox and keep your unsolicited advertising away. This is a simple
+        request.
+    </p>
+    <p>
+        If you send me any kind of spam after this, you have demonstrated that you do not have the basic human decency
+        to respect my wishes or my privacy, and you have lost the privilege for me to respect yours. I
+        <strong>will</strong> block your email address and report you to your email provider. I will also begin to
+        maintain a public blacklist of spammers, so that others may do the same. You will lose all credibility, and you
+        <strong>will</strong> be publicly shamed for it.
+    </p>
+    <p>
+        This <strong>does not apply</strong> to legitimate businesses who are offering something genuine
+        <span style="text-decoration: underline;">to me specifically</span>, nor to individuals who are interested in my
+        services.
+    </p>
+</div>
+
 <form method="post" asp-controller="Contact" asp-action="HandleForm">
     <input type="hidden" name="contact-type" value="other">