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#### Description
- Top span names and Cost by service use `builder_ai_query`, so non-AI
spans no longer show up.
- LLM cost/token panels filter on `gen_ai.request.model EXISTS`; with
variables on "All" they scanned every span.
- Default span mappers now move (not copy) vendor message keys into
`gen_ai.input.messages` / `gen_ai.output.messages`, as documented.
- Bumped versions: dashboard to 3, `gen_ai.llm` mapper to 3,
`gen_ai.agent` mapper to 2.
<!--Reference issues using `Closes #issue-number` to enable automatic
closure on merge. -->
#### Issues closed by this PR
Part of https://github.com/SigNoz/engineering-pod/issues/6107
5a1be60745