test: add unit tests for parsing functions, logger, and utility

Add 34 tests across 3 test files:

- test_browser_agent_parsing.py (20 tests): expand existing tests with
  coverage for extract_links, extract_form, clean_links, parse_answer,
  select_link, jsonify_search_results, stringify_search_results, and
  select_unvisited
- test_logger.py (9 tests): Logger initialization, message writing, log
  level handling, deduplication, and folder creation
- test_utility.py (5 tests): get_color_map returns correct structure and
  color values

All tests avoid LLM requests per issue requirements.

tests/test_utility.py

@@ -0,0 +1,42 @@
+import unittest
+import os
+import sys
+sys.path.insert(0, os.path.abspath(os.path.join(os.path.dirname(__file__), '..')))
+
+from sources.utility import get_color_map
+
+
+class TestUtility(unittest.TestCase):
+    """Test suite for utility module functions."""
+
+    def test_get_color_map_returns_dict(self):
+        """Test that get_color_map returns a dictionary."""
+        color_map = get_color_map()
+        self.assertIsInstance(color_map, dict)
+
+    def test_get_color_map_has_required_keys(self):
+        """Test that color map contains all required color keys."""
+        color_map = get_color_map()
+        required_keys = ["success", "failure", "status", "code", "warning", "output", "info"]
+        for key in required_keys:
+            self.assertIn(key, color_map, f"Missing key: {key}")
+
+    def test_get_color_map_values_are_strings(self):
+        """Test that all color values are strings."""
+        color_map = get_color_map()
+        for key, value in color_map.items():
+            self.assertIsInstance(value, str, f"Value for '{key}' should be a string")
+
+    def test_success_is_green(self):
+        """Test that success maps to green."""
+        color_map = get_color_map()
+        self.assertEqual(color_map["success"], "green")
+
+    def test_failure_is_red(self):
+        """Test that failure maps to red."""
+        color_map = get_color_map()
+        self.assertEqual(color_map["failure"], "red")
+
+
+if __name__ == '__main__':
+    unittest.main()