[TeoSlayer]

Implements @maria-18-git's SGLang metadata diagnosis in #497 and adds regression coverage. Accept nullable completion metadata and the retraction field emitted by SGLang; isolate malformed SSE frames so later valid frames in the same chunk are still decoded. Closes #497.

Schema checked against SGLang 0.5.18's tokenizer manager. All 14 regression cases fail before the fix. Synced with upstream dependency/watchdog fixes, with session startup synchronized in the SIGINT test. Full Linux CI passes; validation uses recorded frames rather than a live GPU-backed SGLang server.

[github-actions]

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[TeoSlayer]

Verified nullable SGLang metadata and recovery after malformed SSE frames. All CI checks pass.

[codecov-commenter]

Codecov Report

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Additional details and impacted files

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  Misses          ?     4218           
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