* fix(proxy): strictly honor disable_end_user_cost_tracking in SpendLogs
* fix(proxy): drop end-user id on failed requests and ClickHouse rows when end-user cost tracking is off
* fix(clickhouse): drop the end-user id from spend log metadata when end-user cost tracking is off
* test(spend): cover disable_end_user_cost_tracking across endpoints, failures, cache hits and chaos
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Co-authored-by: mateo-berri <277851410+mateo-berri@users.noreply.github.com>
* test: migrate legacy unit dirs and unrun folders into tests/unit, tests/integration and tests/e2e
* test: fix disk cache collection, ungate saturation check, drop RSS memory tests
* test: assert one delivered log per completion in Datadog and LangSmith checks
* test: drop SDK-direct e2e copies and align cost-map path filter cases
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Co-authored-by: yuneng <yuneng@berri.ai>
