feat: add theme-aware logo support via optional sourceDark configuration (#6866)

* Initial plan

* Initial exploration and setup

Co-authored-by: aonoa <32682251+aonoa@users.noreply.github.com>

* Add support for separate light and dark theme logos

Co-authored-by: aonoa <32682251+aonoa@users.noreply.github.com>

* Update documentation with dark theme logo configuration

Co-authored-by: aonoa <32682251+aonoa@users.noreply.github.com>

* feat: Add theme-aware logo support for authentication/login page

Co-authored-by: aonoa <32682251+aonoa@users.noreply.github.com>

* revert: .npmrc

Signed-off-by: aonoa <1991849113@qq.com>

---------

Signed-off-by: aonoa <1991849113@qq.com>
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: aonoa <32682251+aonoa@users.noreply.github.com>
Co-authored-by: Li Kui <90845831+likui628@users.noreply.github.com>
Co-authored-by: aonoa <1991849113@qq.com>

packages/@core/preferences/src/types.ts

@@ -146,6 +146,8 @@ interface LogoPreferences {
   fit: 'contain' | 'cover' | 'fill' | 'none' | 'scale-down';
   /** logo地址 */
   source: string;
+  /** 暗色主题logo地址 (可选，若不设置则使用 source) */
+  sourceDark?: string;
 }
 
 interface NavigationPreferences {