v2.10.0

Fixed

• The polling fallback no longer ends the SSE stream. After five consecutive failures — about 31 seconds of unreachability, so an edge incident, a bad deploy or a network partition — SseDataSource handed over to a polling fallback and scheduled no further reconnect, and nothing else re-opened the stream: every affected JVM lost real-time updates until the process restarted, and polled /v1/sdk/flags every 30 seconds indefinitely. Flag changes, kill switches included, then arrived up to a poll interval late. Polling is now additive — it covers the outage while the stream keeps retrying underneath at the capped, jittered backoff, and the next delivered sync retires the poller. Retiring it matters as much as arming it: a poller left running beside a healthy stream reverts SSE deltas with its own whole-store replaces, and a second outage falls back again. (#3071)