fix(web): correct LinkedIn URL on about page

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/cli/src/auth/pairing-code.ts

@@ -0,0 +1,17 @@
+/**
+ * Generate a short pairing code for CLI-to-browser visual confirmation.
+ * Excludes ambiguous characters (0/O, 1/l/I) for readability.
+ */
+
+import { randomBytes } from "node:crypto";
+
+const CHARS = "ABCDEFGHJKLMNPQRSTUVWXYZabcdefghjkmnpqrstuvwxyz23456789";
+
+/**
+ * Generate a 4-character alphanumeric pairing code.
+ * Example output: "A3Kx", "Hn7v", "pQ4m"
+ */
+export function generatePairingCode(): string {
+  const bytes = randomBytes(4);
+  return Array.from(bytes, (b) => CHARS[b % CHARS.length]).join("");
+}