Add version compatibility check before using existing ChromeDriver.
When the installed ChromeDriver major version does not match Chrome,
chromedriver_autoinstaller downloads the correct version automatically
instead of failing with a version mismatch error.
Add helper functions get_chromedriver_version() and
is_chromedriver_compatible() with tests for version matching logic.
Add try-except for json.JSONDecodeError in parse_agent_tasks() to
gracefully handle malformed JSON from LLM responses (e.g. Gemini 2.5
Flash via OpenRouter). Returns empty list on parse failure, which
triggers the existing retry mechanism in make_plan().
Add test suite for parse_agent_tasks() covering valid JSON, malformed
JSON, truncated JSON, and invalid agent name cases.
Br1an67