Add robots.txt blocking all crawlers and AI training bots

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

static/robots.txt

@@ -0,0 +1,35 @@
+User-agent: *
+Disallow: /
+
+User-agent: GPTBot
+Disallow: /
+
+User-agent: Google-Extended
+Disallow: /
+
+User-agent: ClaudeBot
+Disallow: /
+
+User-agent: anthropic-ai
+Disallow: /
+
+User-agent: CCBot
+Disallow: /
+
+User-agent: Bytespider
+Disallow: /
+
+User-agent: PerplexityBot
+Disallow: /
+
+User-agent: FacebookBot
+Disallow: /
+
+User-agent: Applebot-Extended
+Disallow: /
+
+User-agent: cohere-ai
+Disallow: /
+
+User-agent: Amazonbot
+Disallow: /