Fix macOS-flaky tests: testShouldGetLastSessionId and testShouldGetSessionMetadataById

[edburns]

The Copilot CLI persists session state asynchronously, so querying session metadata or the last session ID immediately after sendAndWait() is a race condition. On Linux (CI) and Windows the I/O completes fast enough to mask the issue, but on macOS the tests fail consistently.

Align the Java tests with the .NET and Node.js reference implementations:

• testShouldGetLastSessionId: close the session before calling getLastSessionId() (matches .NET DisposeAsync-then-query pattern), and poll with a 10-second deadline and 50ms intervals (matches Node.js client_lifecycle.e2e.test.ts polling pattern).

• testShouldGetSessionMetadataById: poll getSessionMetadata() with a 10-second deadline and 50ms intervals until it returns non-null (matches .NET WaitForConditionAsync pattern).

[Copilot]

Pull request overview

This PR updates flaky session lifecycle E2E tests to account for Copilot CLI’s asynchronous session persistence, primarily by closing the session before querying the “last session id” and by polling for persisted metadata.

Changes:

• Close the session before querying getLastSessionId(), then poll until the expected ID appears.
• Poll getSessionMetadata(sessionId) until it becomes available (non-null), with a bounded wait window.

Show a summary per file

File	Description
src/test/java/com/github/copilot/sdk/CopilotSessionTest.java	Adds polling/ordering adjustments to reduce macOS-specific flakiness when querying asynchronously persisted session state.

Copilot's findings

Comments suppressed due to low confidence (1)

src/test/java/com/github/copilot/sdk/CopilotSessionTest.java:869

• This loop intends to wait up to 10s, but each getSessionMetadata(...).get(30, TimeUnit.SECONDS) can block for 30s, so the total wait can exceed the deadline significantly if the RPC call is slow/hung. Use a timeout derived from the remaining time (or a small per-call timeout) to ensure the test is actually bounded to ~10s.

            com.github.copilot.sdk.json.SessionMetadata metadata = null;
            long deadline = System.currentTimeMillis() + 10_000;
            while (System.currentTimeMillis() < deadline) {
                metadata = client.getSessionMetadata(sessionId).get(30, TimeUnit.SECONDS);
                if (metadata != null) {
                    break;
                }
                Thread.sleep(50);
            }

• Files reviewed: 1/1 changed files
• Comments generated: 1