test(smoke): mocked critical-path gate that runs keyless on every PR

[jhamon]

What

Propagates the Python SDK's key-free mocked critical-path smoke gate (PIN-75 §2) to the Java SDK. This is the 3rd entry in the PIN-77 rollout (TS → Go → Java → Rust); TS is pinecone-ts-client#395 and Go is go-pinecone#150.

Why

The keyed integration suites (src/integration) can't run on forks or unkeyed PRs, so a regression in the core request/response plumbing can land unnoticed. This gate exercises the real connect → upsert → query path on every PR with no API key.

How

• src/smoke/java/io/pinecone/smoke/MockedCriticalPathTest.java — drives Pinecone.Builder → describeIndex → PineconeConnection + Index → upsert + query with fully in-process mocks:
  • Control plane (describeIndex): OkHttp MockWebServer pointed at via Builder.withHost(...). Real REST request/response path.
  • Data plane (upsert/query): in-process grpc.Server from io.grpc:grpc-testing implementing VectorServiceGrpc.VectorServiceImplBase; channel injected via PineconeConfig.setCustomManagedChannel → PineconeConnection → Index. Real gRPC proto marshaling/unmarshaling runs end to end.
• build.gradle — new smokeTest sourceSet (extends testImplementation) + smokeTest Gradle task with a zero-collection guard (throws GradleException if testCount == 0).
• .github/workflows/pr.yml — new Smoke (mocked, no key) job that runs with no PINECONE_API_KEY on every PR and push to main.
• src/smoke/README.md — documents mocking strategy, local run command, zero-collection guard.

Verification

$ ./gradlew smokeTest
MockedCriticalPathTest > testConnectUpsertQueryAgainstMockedBackend() PASSED
Results: SUCCESS (1 tests, 1 passed, 0 failed, 0 skipped)
# No PINECONE_API_KEY set.

Refs PIN-77.

🤖 Generated with Claude Code

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Note

Low Risk
Changes are limited to smoke tests, Gradle wiring, and CI; production SDK code is unchanged.

Overview
Adds a key-free PR smoke gate that exercises connect → upsert → query without PINECONE_API_KEY, so forks and unkeyed PRs still catch regressions in request/response plumbing before keyed integration tests run.

MockedCriticalPathTest drives the real SDK path with transport-layer mocks: OkHttp MockWebServer + Pinecone.Builder.withHost(...) for describeIndex, and an in-process VectorServiceGrpc server with the channel injected via PineconeConfig.setCustomManagedChannel for upsert/query. Assertions cover responses and on-wire request fields (namespace, topK, vectors).

Build/CI: new smokeTest source set and Gradle task (fails if zero tests run), plus a Smoke (mocked, no key) workflow job on every PR/push to main. src/smoke/README.md documents how to run locally and how this relates to keyed src/integration tests.

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