Follow-ups on the salvaged cluster:
- sse_done.py: dispatch SSE events at blank-line boundaries and join
consecutive data: lines per the SSE spec (a split JSON event no longer
reads as two malformed fragments that disable synthesis)
- accept integer/string-truthy lastOne sentinels (1 / "true") in both the
proxy tracker and the agent stream reader
- server.py: guard the [DONE] append against client hangup at EOF and
widen the interrupt tuple with OSError
- contributor email mappings for loulanyue and jon-nielsen