## Summary
TuShare required non-empty upstream input but filtered fetched news with
the static `keyword` param (default empty string), so agent-provided
keywords were ignored.
Use `self._param.keyword or ans` when filtering, matching how AkShare
uses upstream input for its query.
Fixes#16360
## Test plan
- [x] `test_tushare_filters_with_upstream_keyword_when_param_empty`
mocks the API and asserts only rows matching the upstream keyword are
returned
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Co-authored-by: yzc <yuzhichang@gmail.com>
Co-authored-by: Harsh Kashyap <harshkashyap@Harshs-MacBook-Pro.local>
