Honor configured logger across the request lifecycle

[jackcbrown89]

Summary

• WebSocketSession.handleRequest was replacing the configured logger with a fresh console-based one for every request, so a logger passed via RuntimeUseServerConfig.logger was bypassed for the entire request — including UploadTracker, ArtifactManager, InvocationRunner, the per-command logs, and the agent invocation's logger.
• The fix introduces createPrefixedLogger(inner, prefix) and wraps the configured logger (falling back to defaultLogger) with the source-id prefix and redaction layers, so the user-provided logger receives every per-request line.
• Bumps both packages to 0.15.1.

Test plan

• npm run typecheck
• npm test (151 passing, including two new WebSocketSession > logger tests verifying the configured logger receives prefixed, redacted log lines)

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Note

Low Risk
Low risk: changes are limited to logging plumbing (prefixing/redaction and routing to configured logger) plus version bumps, with new tests covering expected behavior.

Overview
Ensures WebSocketSession.handleRequest routes all per-request logs through the user-provided SessionConfig.logger (falling back to defaultLogger) instead of always creating a fresh console logger.

Introduces createPrefixedLogger(inner, prefix) to apply the source_id tag while preserving the underlying logger, keeps secret redaction via createRedactingLogger, and adds tests verifying configured logger usage and redaction. Bumps package versions to 0.15.1 (Node and Python).

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