chore: change contact page copy from "us/we" to "me/I"

More personal and authentic for a solo POD seller:
- "Get in touch" instead of "Contact Us"
- "Drop me a message" instead of "Drop us"
- "I'll get back to you" instead of "we'll"
- "Send a message" instead of "Send us a message"
- "How can I help?" instead of "How can we help?"
- "I'll send you a link" instead of "we'll send"

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

lib/simpleshop_theme_web/components/page_templates/contact.html.heex

@@ -10,8 +10,8 @@
   <main id="main-content" class="max-w-4xl mx-auto px-4 sm:px-6 lg:px-8 py-16">
     <.hero_section
       variant={:page}
-      title="Contact Us"
-      description="Questions about your order or just want to say hello? Drop us a message and we'll get back to you as soon as we can."
+      title="Get in touch"
+      description="Questions about your order or just want to say hello? Drop me a message and I'll get back to you as soon as I can."
     />
 
     <div class="grid gap-8 md:grid-cols-2 mb-12">