Audit finding 3.1 (high, 3/3 reviewer consensus). Event ids restart at 1
when the backend restarts; a browser auto-reconnect carrying the old
numeric Last-Event-ID was honored whenever the new process had already
emitted that many events, silently suppressing fresh events (same ids,
different content). The previous guard only caught cursor > lastId.
Wire ids are now "<generation>:<seq>" (generation = per-hub instance
token; seq = the existing per-session monotonic counter). The hub parses
raw header/query candidates itself: other-generation and legacy bare-
number cursors are stale → replay from the beginning; same-generation
cursors keep the newest-valid-wins behavior. EventSource treats ids as
opaque, so no frontend change.
Finding 3.2 (eviction) resolved by NOT evicting: close keeps the seq
counter on purpose (sessions reopen; monotonicity is what makes old
cursors detectable) — documented at the call site; buffers are emptied by
clear() and ring-bounded at 200.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
marcopanandClaude Fable 5
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