_max_asset_filename_length of BaseReport does not account for prefixed 'assets/'

The maximum file size is used here to truncate the asset name
https://github.com/pytest-dev/pytest-html/blob/4b88ee41bdbb5666b31dffd366608f735565b329/src/pytest_html/basereport.py#L50

and used together here with 'assets' to build a write destination for media assets
https://github.com/pytest-dev/pytest-html/blob/4b88ee41bdbb5666b31dffd366608f735565b329/src/pytest_html/report.py#L39

on windows systems with a 256 character path length this will cause the write to silently fail and the following read when creating the report to not find the given asset.

conftest.py

@pytest.mark.hookwrapper
def pytest_runtest_makereport(item, call):
    _ = call
    outcome = yield

    report = outcome.get_result()
    extra = getattr(report, 'extra', list())
    report.extra = extra
    browser: WebDriver = item.funcargs.get('browser', None)

    screenshot = browser.get_screenshot_as_base64()
    extra.append(pytest_html.extras.png(screenshot))

test_stuff.py

def test_aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa(browser):
    assert False

Start with the linked calculations in src/pytest_html/basereport.py and src/pytest_html/report.py, then run the provided long-test-name screenshot reproduction on Windows or with an equivalent path-length limit. Done means media assets still write and are read when the generated report uses the prefixed assets/ destination.