fix(xhs): diversify repeated search results

[IRONICBo]

Summary

• Track note IDs returned by earlier searches in the current run.
• Exclude repeated cards while continuing feed collection until enough unique candidates are found.
• Return overlap feedback with specific query angles for the agent loop.
• Cover filtering, current-feed deduplication, and feedback with regression tests.

[vercel]

@IRONICBo is attempting to deploy a commit to the socai Team on Vercel.

A member of the Team first needs to authorize it.

[IRONICBo]

session level dedup：

before:

after:

post id is different in different session.

cc @tonyc-ship

[IRONICBo]

Closing per maintainer request to keep the active delivery queue focused on four PRs only: audio/video integration, Douyin, TikTok, and the consolidated browser self-healing PR #292. This PR remains available in history and can be restored separately if needed.