fix: make Kotlin formatting consistent locally and in CI

[apcha-oai]

Summary

Make Kotlin formatting consistent across developer machines, CI, and SDK updates. Today, scripts/format and scripts/lint select different implementations depending on whether ktfmt is on PATH. The standalone path includes handwritten buildSrc sources, while the Gradle path only checks SDK modules. That lets formatting drift pass CI and later appear as unrelated changes during an SDK update.

Use the repository-pinned Gradle formatter for both entry points, include buildSrc/src in the root Kotlin tasks, and bring the two existing policy files into compliance. This prevents repeat formatting churn without changing SDK behavior or upgrading ktfmt.

Implementation

Share the existing ktfmt task definition between the root project and Kotlin modules. Preserve module-specific tasks and the scripts/kotlin-format entry point, and document the common formatting scope.

[openai-sdks]

OkTest Summary

✅ 237/237 SDK tests passed in 17.335s for Java SDK PR #867.

Test results — 42 files

Test	Result	Time
tests/chat-completions-complex-body.test.ts	✅ Passed	684ms
tests/chat-completions-create.test.ts	✅ Passed	676ms
tests/chat-completions-stream.test.ts	✅ Passed	367ms
tests/files-content-binary.test.ts	✅ Passed	237ms
tests/files-create-multipart.test.ts	✅ Passed	413ms
tests/files-list-pagination.test.ts	✅ Passed	257ms
tests/initialize-config.test.ts	✅ Passed	378ms
tests/instance-isolation.test.ts	✅ Passed	224ms
tests/models-list.test.ts	✅ Passed	173ms
tests/responses-background-lifecycle.test.ts	✅ Passed	311ms
tests/responses-body-method-errors.test.ts	✅ Passed	529ms
tests/responses-cancel-timeout.test.ts	✅ Passed	233ms
tests/responses-cancel.test.ts	✅ Passed	410ms
tests/responses-compact-retries.test.ts	✅ Passed	484ms
tests/responses-compact.test.ts	✅ Passed	408ms
tests/responses-create-advanced-stream.test.ts	✅ Passed	319ms
tests/responses-create-advanced.test.ts	✅ Passed	1.307s
tests/responses-create-disconnect.test.ts	✅ Passed	1.189s
tests/responses-create-errors.test.ts	✅ Passed	376ms
tests/responses-create-malformed-api-responses.test.ts	✅ Passed	333ms
tests/responses-create-retries.test.ts	✅ Passed	339ms
tests/responses-create-stream-failures.test.ts	✅ Passed	212ms
tests/responses-create-stream-timeout.test.ts	✅ Passed	243ms
tests/responses-create-stream-wire.test.ts	✅ Passed	6.489s
tests/responses-create-stream.test.ts	✅ Passed	420ms
tests/responses-create-terminal-states.test.ts	✅ Passed	423ms
tests/responses-create-timeout.test.ts	✅ Passed	238ms
tests/responses-create.test.ts	✅ Passed	863ms
tests/responses-delete.test.ts	✅ Passed	268ms
tests/responses-input-items-errors.test.ts	✅ Passed	286ms
tests/responses-input-items-list.test.ts	✅ Passed	309ms
tests/responses-input-items-options.test.ts	✅ Passed	199ms
tests/responses-input-tokens-count-timeout.test.ts	✅ Passed	249ms
tests/responses-input-tokens-count.test.ts	✅ Passed	405ms
tests/responses-malformed-inputs.test.ts	✅ Passed	5.291s
tests/responses-not-found-errors.test.ts	✅ Passed	428ms
tests/responses-parse.test.ts	✅ Passed	672ms
tests/responses-retrieve-retries.test.ts	✅ Passed	394ms
tests/responses-retrieve.test.ts	✅ Passed	429ms
tests/responses-stored-method-errors.test.ts	✅ Passed	1.071s
tests/retry-behavior.test.ts	✅ Passed	3.537s
tests/sdk-error-shape.test.ts	✅ Passed	403ms

View OkTest run #31995497724

_{SDK merge (ba5931eae50a) · head (c94f53c33b92) · base (fcdcc7ee0414) · OkTest (7e7850017529)}