Brent pla 1693 more logging and v3.9.0

[jareddellitt]

Describe the solution you've provided
Add additional logging and updated otp version

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Note

Medium Risk
Changes touch the live streaming reconnect path and may log SSE FIN payloads; CI-only OTP addition is low risk but expands the compatibility surface.

Overview
Adds OTP 28.4.1 (with matching rebar) to the GitHub Actions build matrix so the SDK is tested on the newest supported Erlang.

In ldclient_update_stream_server, observability around the LaunchDarkly SSE/Shotgun path is expanded: the process sets logger metadata on init, logs when a Shotgun connection is established, and starts a 1s check_shotgun_state poll that warns if Shotgun is {down, _} before the client’s DOWN handling kicks in (with an info log when there is no connection to poll). SSE fin callbacks now log the ignored payload via ?LOG_INFO before closing and reconnecting.

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[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

^{Reviewed by Cursor Bugbot for commit 0ed3fc1. Configure here.}

[cursor]

Shotgun poll message mismatch

Medium Severity

The Shotgun health poll schedules its next tick with {check_shotgun_state} while handle_info only handles the atom check_shotgun_state. After the first poll (~1s after connect), later messages no longer match those clauses and are dropped by the generic handle_info, so the new “silent failure” polling never continues.

 

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