fix(web-ui): tolerate missing model identity in model-round events - #1936
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The ACP client emitter builds agentic://model-round-started payloads by hand and does not carry modelConfigId/effectiveModelName, which the native projection always provides. Since 4d73585 the UI treated these fields as required and called .trim() unconditionally, so external ACP agent rounds threw on start, no ModelRound was created, and subsequent text-chunk/tool events were dropped - leaving the transcript empty while the agent kept working. Make both fields optional on the event contracts and omit them from the round when absent instead of fabricating placeholder values. The subagent parent task model update now reads from the created round and only runs when a model name exists.
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Problem
When BitFun runs as an ACP client chatting with an external ACP agent (Codex, Claude Code, etc.), the FlowChat transcript stays empty: the agent keeps running, permission prompts may appear, files may be modified, but assistant text / tool results never show up.
Root cause
Since commit 4d73585 ("feat(agentic): support configurable subagent models"),
handleModelRoundStartinEventHandlerModule.tstreatsmodelConfigIdandeffectiveModelNameas required and calls.trim()on them unconditionally. The nativeAgenticEvent::ModelRoundStartedprojection always carries both fields, but the ACP client emitter (acp_client_api.rs) builds theagentic://model-round-startedpayload by hand and does not include them.Failure chain:
.trim()onundefinedthrows a TypeError.ModelRoundis created for that round.agentic://text-chunk/ tool events look up the round viaaddModelRoundItemand are dropped ("Model round not found").Fix
modelConfigId/effectiveModelNameoptional onModelRoundStartedEventandModelRoundCompletedEvent(AgentAPI.ts).ModelRoundwhen absent instead of fabricating placeholder values (external ACP agents have no BitFun model identity).updateSubagentParentTaskModelreads from the created round and only runs when a model name is present.Verification
pnpm --dir src/web-ui run test:run src/flow_chat/services/flow-chat-manager/EventHandlerModule.test.ts- 25/25 passedpnpm run type-check:web- passed