refactor(akka-apps): remove dead bbb-html5 -> akka-apps messages

[antobinary]

What this does

Closes bigbluebutton#20095 — removes the client → akka-apps messages that no longer have a
sender, and the outbound messages they leave stranded.

The html5 client stopped publishing to redis when its calls moved to
bbb-graphql-actions, and state reads moved to GraphQL/Hasura. Anything
ReceivedJsonMsgHandlerActor still accepts but nobody sends is dead code.

44 messages removed.

	Before	After
Inbound messages accepted by akka-apps	208	179
Messages defined in bbb-common-message	447	406

Two commits, so the risky part is reviewable on its own:

Commit	Contents	Diff
0da4f75746	3 inbound (pads + waiting queue)	10 files, −124
43351d1fbb	26 inbound + 15 stranded outbound	55 files, +16 / −1163

Inbound removed (29)

Initial-state fetches (13) — the client reads this from Hasura now:
GetAllPresentationPodsReqMsg, GetChatHistoryReqMsg, GetCurrentLayoutReqMsg,
GetCurrentPollReqMsg, GetGroupChatMsgsReqMsg, GetGroupChatsReqMsg,
GetGuestPolicyReqMsg, GetGuestsWaitingApprovalReqMsg,
GetPresenterGroupReqMsg, GetScreenshareStatusReqMsg,
GetWebcamsOnlyForModeratorReqMsg, GetWhiteboardAnnotationsReqMsg,
IsMeetingMutedReqMsg

Chat (2), superseded by group chat in 2018 — SendPublicMessagePubMsg,
SendPrivateMessagePubMsg

Presenter group (2), feature removed 2018 — AddUserToPresenterGroupCmdMsg,
RemoveUserFromPresenterGroupCmdMsg

Presentation pods (4) — CreateNewPresentationPodPubMsg,
RemovePresentationPodPubMsg, SlideResizedPubMsg,
PreuploadedPresentationsSysPubMsg

Pads / waiting queue (3) — PadCreateReqMsg, PadUpdatePubMsg,
UpdatePositionInWaitingQueueReqMsg

Other (5) — BreakoutRoomsListMsg, LockUsersInMeetingCmdMsg,
EjectUserFromMeetingSysMsg, RecordAndClearPreviousMarkersCmdMsg,
ClientToServerLatencyTracerMsg

Outbound removed (15)

These lost their only emitter when the inbound side went, so they are removed in
the same change rather than left as new dead code:

GetAllPresentationPodsRespMsg, GetChatHistoryRespMsg,
GetCurrentLayoutRespMsg, GetCurrentPollRespMsg, GetGroupChatMsgsRespMsg,
GetGroupChatsRespMsg, GetGuestPolicyRespMsg,
GetWebcamsOnlyForModeratorRespMsg, GetWhiteboardAnnotationsRespMsg,
IsMeetingMutedRespMsg, NewPresentationEvtMsg, SendPrivateMessageEvtMsg,
ServerToClientLatencyTracerMsg, PadUpdateCmdMsg,
PosInWaitingQueueUpdatedRespMsg

Plus the helpers that built them: Polls.handleGetCurrentPollReqMsg,
PresentationApp2x.processPreuploadedPresentations, the
NewPresentationMsgHdlr trait, MsgBuilder.buildPosInWaitingQueueUpdatedRespMsg,
and the GuestWaitingUP VO that only PosInWaitingQueueUpdatedRespMsg used.

Verified invariant: 25 messages in bbb-common-message have no emitter after
this PR, and all 25 were already in that state on v4.1.x-develop. No message
that had an emitter before this change is left without one.

Notes for reviewers

LayoutApp2x now declares val liveMeeting: LiveMeeting itself. It inherited
that declaration from GetCurrentLayoutReqMsgHdlr, and its sibling handler
traits resolve liveMeeting through the mixin.

Pad creation is unaffected — akka-apps drives it via
PadslHdlrHelpers.broadcastPadCreateGroupCmdMsg / broadcastPadCreateCmdMsg
from MeetingActor and PadGroupCreatedEvtMsgHdlr. PadCreateReqMsg was only
the old client-initiated entry point.

bbb-pads still has a redis handler for PadUpdateCmdMsg
(lib/redis/handler.js). Nothing has emitted that message since the client
stopped sending PadUpdatePubMsg, so the handler was already unreachable; it can
be dropped on the bbb-pads side separately.

Deliberately NOT removed

GetMediaGroupsReqMsg has no sender either, but it is not legacy. Added
2024-12 as GetAudioGroupsReqMsg, renamed 2025-10 when media groups were
extended to cameras and screenshare; its sibling graphql-actions mutations
(mediaGroupCreate/Destroy/Join/Leave/UpdateParticipant) are all live. Looks
like scaffolding for in-flight work — @prlanzarin should confirm before it goes.

UserConnectedToGlobalAudioMsg / UserDisconnectedFromGlobalAudioMsg look
dead from this repo but bbb-webrtc-sfu sends both from
lib/audio/client-audio-consumer.js.

TranscriptionProviderErrorMsg — sent by bbb-transcription-controller
(app.js:199).

CheckGraphqlMiddlewareAlivePongSysMsg, UserGraphqlConnectionEstablishedSysMsg,
UserGraphqlConnectionClosedSysMsg — sent by bbb-graphql-middleware (Go).

How "no sender" was established

A grep of this repo is not sufficient — several of the near-misses above are sent
from other repos. Each candidate was checked against:

• every component in this monorepo, including akka-apps constructing the message
  itself, not just handling it;
• the components installed on a running 4.x server (bbb-webrtc-sfu, bbb-pads,
  bbb-export-annotations, bbb-graphql-actions, etherpad incl.
  ep_redis_publisher, the Ruby recording scripts, freeswitch);
• jar/war contents via unzip -p | strings;
• the bbb-graphql-middleware and bbb-webrtc-recorder Go binaries via strings
  (substring, not anchored — Go concatenates string literals);
• bbb-transcription-controller v0.2.10, bbb-webhooks v3.6.1 and
  bbb-webrtc-recorder v0.14.0 at their pinned placeholder tags;
• every publisher to to-akka-apps-redis-channel, to confirm none builds a
  message name dynamically;
• docs/, in case any is a documented integration point;
• git log -S per message, for senders removed recently enough to be coming back.

A second independent pass re-ran all of this adversarially, instructed to refute
rather than confirm. It is what rescued GetMediaGroupsReqMsg.

Testing

• bbb-common-message — sbt publishM2 succeeds.
• akka-bbb-apps — sbt compile succeeds; only pre-existing deprecation warnings.
• akka-bbb-apps — sbt test does not compile on v4.1.x-develop, with or
  without this change: 54 identical errors in TestDataGen.scala
  (RegisteredUsers.create missing loggedOut; WebcamStream missing
  hasAudio/showAsContent/subscribers). Verified by stashing the change and
  re-running. Filed separately; not addressed here.
• The MeetingActor diff was reviewed arm by arm: multi-line case m: X =>
  bodies are removed together with their case line. An earlier scripted attempt
  dropped only the case line and silently merged the body into the previous
  arm — it compiled and was wrong. Worth spot-checking in review.

Follow-ups

• 25 messages in bbb-common-message have no emitter and predate this PR —
  separate issue.
• bbb-graphql-middleware sends UserGraphqlDisconnectionForcedEvtMsg, which
  akka-apps has never had a handler for — separate issue.
• akka-bbb-apps test suite does not compile — separate issue.

[antobinary]

Issue 1 — dead outbound messages


Remove dead outbound messages from bbb-common-message

Mirror of bigbluebutton#20095. That issue covered inbound (client → apps) messages with no
sender; this covers messages that are defined but never emitted.

Of 421 messages currently defined in bbb-common-message, 25 are referenced
nowhere outside their own definition — not in akka-apps, akka-fsesl, bbb-web,
bbb-common-web, bbb-graphql-actions, bbb-shared-notes-server, the html5 client,
bbb-pads, or record-and-playback. Several are also absent from the components
installed on a running 4.x server and from the bbb-graphql-middleware binary.

Request/response pairs whose request side is long gone

GetLockSettingsRespMsg          LockSettingsNotInitializedRespMsg
GetPresenterGroupRespMsg        GetUsersReqMsg
LookUpUserRespMsg               UserSessionTokenRegisteredRespMsg

Group chat events, superseded

GroupChatAccessChangedEvtMsg    GroupChatUserAddedEvtMsg
GroupChatDestroyedEvtMsg        GroupChatUserRemovedEvtMsg
OpenGroupChatWindowEvtMsg

Pads

CaptureSharedNotesReqEvtMsg     PadCapturePubMsg
PadGroupCreatedRespMsg          PadTailEvtMsg

Presentation conversion progress events

PresentationConversionRequestReceivedEventMsg
PresentationPageConversionStartedEventMsg
PresentationUploadedConversionCancelledErrorEvtMsg

Other

CamStreamSubscribeSysMsg        PubSubPingSysReqMsg
TimerEndedPubMsg                PubSubPongSysRespMsg
TransferUserToMeetingEvtMsg     ServerToClientLatencyTracerMsg
UserGraphqlDisconnectionForcedEvtMsg   (see separate issue — middleware sends it)
UserGraphqlReconnectionForcedEvtMsg

Caveats for whoever picks this up

• A repo grep is not sufficient. While working Remove all bbb-html5 -> akka-apps bbb-common-messages bigbluebutton/bigbluebutton#20095, three messages that
  looked dead here turned out to be sent from other repos: bbb-webrtc-sfu
  (UserConnectedToGlobalAudioMsg), bbb-transcription-controller
  (TranscriptionProviderErrorMsg) and bbb-graphql-middleware. Check the
  installed components, the Go binaries with strings, and the placeholder
  repos at their pinned tags before deleting anything.
• The presentation-conversion events are the ones I'd scrutinise hardest — they
  look like progress reporting that a UI or the recording pipeline might have
  consumed.
• Some of these have consumers even though nothing emits them (see the
  separate middleware issue). A consumer without an emitter is a dead feature,
  which may be a bug rather than something to delete.
  Issue 2 — a message sent into the void
  

bbb-graphql-middleware sends UserGraphqlDisconnectionForcedEvtMsg but akka-apps has no handler

bbb-graphql-middleware publishes UserGraphqlDisconnectionForcedEvtMsg to
redis — the symbol websrv.SendUserGraphqlDisconnectionForcedEvtMsg is present
in the shipped binary, confirmed with strings /usr/bin/bbb-graphql-middleware.

akka-apps never handles it. It is not in ReceivedJsonMsgHandlerActor's
dispatch, and the name appears nowhere in akka-bbb-apps at all.
git log -S UserGraphqlDisconnectionForcedEvtMsg -- akka-bbb-apps/ is empty, so
a handler has never existed on this branch.

The message is defined in bbb-common-message
(SystemMsgs.scala:208) with body
(middlewareUID: String, sessionToken: String, browserConnectionId: String).

UserGraphqlReconnectionForcedEvtMsg is defined alongside it and is likewise
unreferenced in akka-apps, though I did not find a sender for that one.

So either:

• akka-apps is meant to react to a forced graphql disconnection and the handler
  was never wired up — in which case something is silently not happening; or
• the message is genuinely obsolete, and the middleware should stop publishing it
  and both definitions should be removed.

Worth a maintainer deciding which, rather than assuming. Found while working
bigbluebutton#20095.
Issue 3 — the test suite doesn't build


akka-bbb-apps test suite does not compile on v4.1.x-develop

sbt test in akka-bbb-apps fails with 54 compilation errors before any test
runs. Reproduced on a clean checkout of v4.1.x-develop (13c457f).

Two model signatures drifted away from the test fixtures:

src/test/scala/org/bigbluebutton/core2/testdata/TestDataGen.scala:20

not enough arguments for method create: (..., livekitToken: Option[String])
  Unspecified value parameter loggedOut.
    val ru = RegisteredUsers.create(meetingId, userId = id, extId, name, "", "", role, ...

src/test/scala/org/bigbluebutton/core2/testdata/TestDataGen.scala:85

not enough arguments for method apply: (streamId, userId, contentType, hasAudio,
  showAsContent, subscribers) in object WebcamStream.
  Unspecified value parameters hasAudio, showAsContent, subscribers.
    WebcamStream(streamId, userId, subscribers)

Also touches AppsTestFixtures.scala, BigBlueButtonActorTestsSpec.scala and
TestKitUsageSpec.scala.

Impact: there is currently no automated test coverage for akka-apps —
sbt compile succeeds, so this does not show up unless you run the tests.

Note that sbt reformats the test sources via scalariform on compile, so a test
run leaves the working tree dirty even when it fails.

[github-actions]

🚨 Automated tests failed

• Github workflow run