feat: deployment costs endpoint

[vladyslavchuhai-spec]

Applicable issues

• fixes/implements [Eval] [spike] research requirements for Evaluatee analytics page #65

Description of changes

Problem

Cost analytics existed only per test-suite run (GET /api/v1/test-suite-runs/{id}/costs, average cost per call), so there was no way to answer "how much has this deployment cost over a given period?" — e.g. spend for the current or previous month across all runs. The existing logic also lived inside TestSuiteRunService, which already owns run lifecycle concerns, and the dial-adas query filtered on a json_extract_string(request_tags, 'baggage') expression that no longer matches the upstream usage-log schema.

Solution

Added GET /api/v1/costs?deploymentId&from&to (inclusive epoch-millisecond range) returning totalTestCaseCost and totalMetricEvalCost — sum(total_price) per execution phase — via a new CostController + DeploymentCostsResponseDto, with 400 on blank deploymentId or from > to and the existing 502/504 upstream mapping. All cost logic moved out of TestSuiteRunService into a dedicated CostService (reaching run-existence validation through TestSuiteRunService.ensureRunExists, not the repository, per the cross-domain rule), and RunCostQueryBuilder was generalized into AdasCostQueryBuilder with run-scoped (baggage-filtered avg) and deployment-scoped (deployment + request_time columns, sum) aggregate queries. Baggage filtering was corrected to the real usage_request_baggage.baggage field. Includes unit tests for the new builder, service and controller, a functional test, OpenAPI examples, and spec/doc updates.

Checklist

• corresponding issue(s) linked in the "Development" section of sidebar and referenced in "Applicable issues" section above
• I have read the "Description of changes" and understood it

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[ai-dial-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

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