* fix(search): accept CLI queries that look like numbers
The CLI parses key=value arguments into typed values, so query=404 reached the search steps as an int and failed on .strip(), and query=NaN or query=Infinity became non-finite floats that the HTTP client cannot encode as JSON and the MCP client sends as null.
Read the query as text in the four search steps, as ChatStep already does, and keep values that float() reads as NaN or infinity as strings.
* fix(search): treat only a missing query as empty
str(query or "") turned query=0 and query=0.0 into an empty string, so those searches still failed with "query cannot be empty". Check for None before converting instead.
The BEAM and LME plugins replace the default search job with their own SearchV2Step, which still called .strip() on the raw value, so query=404 raised AttributeError when either plugin was enabled. Read the query the same way there.
The numeric-query test is now parametrized over the six steps and passes 404, 0 and 0.0 through parse_kwargs first.
* refactor(plugins): move BaseAgenticAnswerStep into lme/beam plugins
Move the shared benchmark answer base class from the core
reme.steps.benchmark package into each plugin's own src tree
(reme_lme.base_agentic_answer / reme_beam.base_agentic_answer) with
absolute imports, drop the core benchmark steps package, and update
plugin READMEs accordingly.
* refactor(plugins): simplify benchmark answer steps
* docs(plugins): clarify benchmark answer step migration
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Co-authored-by: jinli.yl <jinli.yl@alibaba-inc.com>
