chore(release): prepare 2.0.0-Beta.2 build 20260924

Integrate the reviewed 2.0 PRs and local fixes from 03136853.
Preserve the verified subtitle behavior and model/runtime corrections.
Keep the numeric Beta tag compatible with released clients while exposing
the date as application build metadata.

Co-authored-by: DepengWang <2818245+DepengWang@users.noreply.github.com>
Co-authored-by: HKLHaoBin <we3q@qq.com>
Co-authored-by: Nahida <1139500183@qq.com>
Co-authored-by: TRIP <1933142963@qq.com>
Co-authored-by: chyuwei <weichangyuwcy@gmail.com>
Co-authored-by: leonoxo <leonoxo@gmail.com>
Co-authored-by: tayir <arnoldincredible@126.com>

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