test: add end-to-end Q7 map_content.refresh coverage

[arduano]

Openclaw:

Summary

• replace the Q7 map_content.refresh() test that mocked B01MapParser.parse
• use a real encrypted MAP_RESPONSE payload built from the checked-in SCMap fixture
• assert the full parse/render/cache path by checking PNG output, parsed map_data, and room-name extraction

Why

PR Python-roborock#785 deferred concern: existing test didn't exercise the real Q7 map-content decode/parse/render path.

Validation

• . .venv/bin/activate && pytest -q tests/devices/traits/b01/q7/test_map_content.py tests/map/test_b01_map_parser.py
• ruff check tests/devices/traits/b01/q7/test_map_content.py