feat: add llms.txt detection module

tests/test_llms_txt_detector.py

@@ -0,0 +1,13 @@
+import pytest
+from cli.llms_txt_detector import LlmsTxtDetector
+
+def test_detect_llms_txt_variants():
+    """Test detection of llms.txt file variants"""
+    detector = LlmsTxtDetector("https://hono.dev/docs")
+
+    # Mock responses
+    variants = detector.detect()
+
+    assert variants is not None
+    assert 'url' in variants
+    assert 'variant' in variants  # 'full', 'standard', 'small'