Enhance SEO and feedback features across the application

- Updated index.html with improved meta tags for SEO, including author and theme color.
- Added a feedback dialog in ImprintContainer.vue for user feedback submission.
- Refactored LoginForm.vue to utilize a utility for cookie management, simplifying profile persistence.
- Introduced new routes and schemas for feedback in the router and server, enhancing SEO and user experience.
- Improved ChatView.vue with better error handling and command table display.
- Implemented feedback API endpoints in server routes for managing user feedback submissions and admin access.

These changes collectively improve the application's SEO, user interaction, and feedback management capabilities.

client/src/views/FeedbackView.vue

@@ -0,0 +1,22 @@
+<template>
+  <div class="chat-container">
+    <header class="header">
+      <div class="app-brand">
+        <span class="app-brand-mark">S</span>
+        <div class="app-brand-copy">
+          <span class="app-brand-eyebrow">SingleChat</span>
+          <h1>Feedback</h1>
+        </div>
+      </div>
+    </header>
+
+    <FeedbackPanel />
+
+    <ImprintContainer />
+  </div>
+</template>
+
+<script setup>
+import FeedbackPanel from '../components/FeedbackPanel.vue';
+import ImprintContainer from '../components/ImprintContainer.vue';
+</script>