Fix dashboard room thread chunk rendering (#65)

* review: harden readonly git checks and lint verification

* test: satisfy readonly reviewer sandbox typing

* test: fix readonly reviewer sandbox assertions

* test: remove impossible readonly sandbox guards

* test: relax readonly sandbox assertions

* test: cast readonly sandbox expectation shape

* test: cast readonly sandbox expectation through unknown

* Phase 0 — STEP_DONE/TASK_DONE split + owner-follow-up integration smoke

* Add STEP_DONE guards, verdict storage, and stale delivery suppression

* style: format paired stepdone telemetry files

* Route STEP_DONE through reviewer

* Add structured Discord attachments

* style: format structured attachment test

* Fix room thread bot output parity

* Remove duplicate work item attachment migration from owner branch

* Remove legacy dashboard rooms renderer

* Extract dashboard parsed body renderer

* Extract dashboard redaction helpers

* Extract dashboard RoomCardV2 component

* Include RoomCardV2 test in vitest suite

* Extract dashboard RoomBoardV2 component

* Extract dashboard EmptyState component

* Extract dashboard InboxPanel component

* Split dashboard InboxPanel card renderer

* Extract dashboard TaskPanel component

* Extract dashboard UsagePanel component

* Fix dashboard room thread chunk rendering

apps/dashboard/src/roomThread.ts

@@ -81,6 +81,11 @@ function normalizeForDedupe(value: string): string {
   return value.replace(/\s+/g, ' ').trim();
 }
 
+const MIN_SUBSTRING_DEDUPE_LENGTH = 40;
+const BOT_CHUNK_MERGE_WINDOW_MS = 15_000;
+const STATUS_OUTPUT_PREFIX_RE =
+  /^(?:STEP_DONE|TASK_DONE|DONE_WITH_CONCERNS|DONE|BLOCKED|NEEDS_CONTEXT)\b/;
+
 function isDuplicateOutputMessage(
   message: RoomThreadEntry,
   outputEntries: RoomThreadEntry[],
@@ -96,7 +101,11 @@ function isDuplicateOutputMessage(
     const contentMatches =
       outputText === messageText ||
       outputText.startsWith(messageText) ||
-      messageText.startsWith(outputText);
+      messageText.startsWith(outputText) ||
+      (messageText.length >= MIN_SUBSTRING_DEDUPE_LENGTH &&
+        outputText.includes(messageText)) ||
+      (outputText.length >= MIN_SUBSTRING_DEDUPE_LENGTH &&
+        messageText.includes(outputText));
     if (!contentMatches) return false;
     const outputTime = new Date(output.timestamp).getTime();
     if (!Number.isFinite(messageTime) || !Number.isFinite(outputTime)) {
@@ -106,6 +115,57 @@ function isDuplicateOutputMessage(
   });
 }
 
+function entryTimeMs(entry: RoomThreadEntry): number | null {
+  const time = new Date(entry.timestamp).getTime();
+  return Number.isFinite(time) ? time : null;
+}
+
+function shouldMergeAdjacentBotChunk(
+  previous: RoomThreadEntry,
+  next: RoomThreadEntry,
+): boolean {
+  if (
+    previous.sourceKind === 'agent_output' ||
+    next.sourceKind === 'agent_output'
+  ) {
+    return false;
+  }
+  if (previous.senderName !== next.senderName) return false;
+  if (previous.sourceKind !== next.sourceKind) return false;
+  if (!previous.isBotMessage || !next.isBotMessage) return false;
+  if (STATUS_OUTPUT_PREFIX_RE.test(next.content.trimStart())) return false;
+  const previousTime = entryTimeMs(previous);
+  const nextTime = entryTimeMs(next);
+  if (previousTime === null || nextTime === null) {
+    return previous.timestamp === next.timestamp;
+  }
+  return Math.abs(nextTime - previousTime) <= BOT_CHUNK_MERGE_WINDOW_MS;
+}
+
+function mergeEntryContent(left: string, right: string): string {
+  const trimmedLeft = left.trimEnd();
+  const trimmedRight = right.trimStart();
+  if (!trimmedLeft) return trimmedRight;
+  if (!trimmedRight) return trimmedLeft;
+  return `${trimmedLeft}\n\n${trimmedRight}`;
+}
+
+function mergeAdjacentBotChunks(entries: RoomThreadEntry[]): RoomThreadEntry[] {
+  const merged: RoomThreadEntry[] = [];
+  for (const entry of entries) {
+    const previous = merged.at(-1);
+    if (previous && shouldMergeAdjacentBotChunk(previous, entry)) {
+      previous.id = `${previous.id}+${entry.id}`;
+      previous.content = mergeEntryContent(previous.content, entry.content);
+      previous.verdict ??= entry.verdict;
+      previous.turnNumber ??= entry.turnNumber;
+      continue;
+    }
+    merged.push({ ...entry });
+  }
+  return merged;
+}
+
 export function buildRoomThreadEntries({
   messages,
   outputs,
@@ -128,7 +188,8 @@ export function buildRoomThreadEntries({
     .filter((message) => !isInternalProtocolPayload(message.content))
     .map(toMessageEntry);
 
-  return [...chatEntries, ...optimisticPending, ...outputEntries].sort((a, b) =>
-    a.timestamp.localeCompare(b.timestamp),
+  const entries = [...chatEntries, ...optimisticPending, ...outputEntries].sort(
+    (a, b) => a.timestamp.localeCompare(b.timestamp),
   );
+  return mergeAdjacentBotChunks(entries);
 }