The new "添加模型提供商" button shares a prefix with the Models nav entry,
so every e2e that clicked the nav through a non-exact locator resolved
two buttons once the page rendered; the nav locators are exact now.
The vendor sense of "provider" is registered in the terminology table
as 模型提供商 with its scope — the Models settings copy, the providers
user guide, and this package's README — while the generic provider rows
keep 提供方, and the package's Chinese README uses the vendor term
throughout. The custom card's header comment no longer claims a mode
switch that a custom-only card does not render, and the SegmentedControl
suite gains a positive Home/End case whose first enabled option is not
the first option.