* Refactor exemplars to not use generic argument
* Update internal/aggregate
* Update metric SDK
* Test exemplar value type
* Add TestCollectExemplars
* Fix lint
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Co-authored-by: Sam Xie <sam@samxie.me>
* Add the experimental exemplar feature
* Add exemplars to EXPERIMENTAL.md
* Add changelog entry
* Fix hist buckets > 1 detection
* Collect instead of Flush res about to be deleted
* Add e2e test
* Do not pre-alloc ResourceMetrics
This only has a single use.
* Fix grammatical error in comment
* Add test cases
Default and invalid OTEL_METRICS_EXEMPLAR_FILTER.
Test sampled and non-sampled context for trace_based.
* Comment nCPU
* Doc OTEL_METRICS_EXEMPLAR_FILTER