Add a pytest-discovered tests/conftest.py for the last30days scripts path and
remove duplicate per-file sys.path.insert boilerplate from tests.
Normalize affected imports to rely on the shared scripts path and remove the
now-unneeded E402 suppressions.
Brave uses identical v10 AES-128-CBC encryption to Chrome; only the
DB path (BraveSoftware/Brave-Browser) and Keychain service name
("Brave Safe Storage") differ. Refactored chrome_cookies.py to share
a single _extract_chromium_cookies_macos helper rather than duplicating
the decryption logic.
Profile discovery tries Default/ first, then scans numbered Profile N/
directories so non-default Brave profiles are covered.