fix(console): isolate workflow SSE request callbacks

[lyj715824]

Summary

• scope workflow SSE callbacks to their originating request
• ignore delayed messages, errors, and close events from superseded streams
• replace source-text assertions with runtime overlap regression tests

Validation

• node --test --loader ts-node/esm tests/sse-request.test.js
• ESLint on changed workflow SSE files
• npm run build-prod

[gemini-code-assist]

Caution

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