chore: remove outdated OAuth setup documentation and update favicon

- Deleted the `oauth-setup.md` file as it contained outdated information regarding OAuth configuration.
- Updated the favicon in `favicon.svg` to a new design for improved branding and visual appeal.
- Enhanced the `index.html` file with additional meta tags for better SEO and social media sharing.

Author: rithulkamesh

docs/oauth-setup.md

@@ -5,6 +5,17 @@
     <link rel="icon" type="image/svg+xml" href="/favicon.svg" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
     <title>Devsper Plugin Registry</title>
+    <meta name="description" content="Discover and install plugins for the devsper AI swarm runtime. The AI swarm platform for developers." />
+    <meta property="og:title" content="Devsper Plugin Registry" />
+    <meta property="og:description" content="Discover and install plugins for the devsper AI swarm runtime. The AI swarm platform for developers." />
+    <meta property="og:image" content="https://registry.devsper.com/og.png" />
+    <meta property="og:url" content="https://registry.devsper.com/" />
+    <meta property="og:type" content="website" />
+    <meta property="og:locale" content="en_US" />
+    <meta name="twitter:card" content="summary_large_image" />
+    <meta name="twitter:title" content="Devsper Plugin Registry" />
+    <meta name="twitter:description" content="Discover and install plugins for the devsper AI swarm runtime. The AI swarm platform for developers." />
+    <meta name="twitter:image" content="https://registry.devsper.com/og.png" />
     <link rel="preconnect" href="https://fonts.googleapis.com" />
     <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin />
     <link