[KQL] Migrate value suggestions API tests from FTR to Scout

[shahzad31]

Summary

Migrates the platform apis/suggestions FTR API-integration suite (the
value suggestions / autocomplete endpoint, POST /internal/kibana/suggestions/values/{index})
to a Scout API suite, co-located with the route owner — the kql plugin.

This:

• Aligns test ownership with code ownership. The old FTR path was owned by
  @elastic/actionable-obs-team purely as a best-effort backfill artifact
  (#200950), even though the
  route lives in kql. Placing the tests under
  src/platform/plugins/shared/kql/test/scout/api makes them auto-inherit
  the kql CODEOWNERS entry (@elastic/kibana-presentation).
• Removes a legacy stateful-only FTR config.

What changed

• Added src/platform/plugins/shared/kql/test/scout/api — a Scout API suite
  (@kbn/scout) with all 12 cases ported 1:1, split across:
  • value_suggestions.spec.ts (8) — non-time-based behavior over basic_index
    (terms_agg / terms_enum, special characters, nested fields, 404/400 cases).
  • value_suggestions_time_filters.spec.ts (4) — time-based filter behavior over
    logstash-* (document-level vs index-level filtering).
• Deleted src/platform/test/api_integration/apis/suggestions and removed it
  from the api_integration index.
• Registered kql in .buildkite/scout_ci_config.yml (done by the generator).
• Removed the now-stale CODEOWNERS entry for the old FTR path.

Notes

• Fixes a latent bug from the original FTR suite: the last time-based test never
  returned/awaited its supertest chain, so its assertion couldn't fail. The Scout
  version awaits it properly.
• The Scout esArchiver fixture only ingests data (no unload), so cleanup only
  removes the imported Kibana saved objects.

Test plan

• node scripts/type_check --project src/platform/plugins/shared/kql/test/scout/api/tsconfig.json
• node scripts/eslint on changed files
• node scripts/scout.js run-tests --arch stateful --domain classic --config src/platform/plugins/shared/kql/test/scout/api/playwright.config.ts → 12/12 passed
• node scripts/check.js --scope branch → lint ✓, jest (no affected configs), tsc ✓ (47 projects)

Made with Cursor

[infra-vault-gh-plugin-prod]

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