Method flushPartialWrite

src/node/services/streamManager.ts:765–796

* Flush any pending partial write and write immediately * Serializes writes to prevent races - waits for any in-flight write before starting new one

(
    workspaceId: WorkspaceId,
    streamInfo: WorkspaceStreamInfo
  )

   * Serializes writes to prevent races - waits for any in-flight write before starting new one
   */
  private async flushPartialWrite(
    workspaceId: WorkspaceId,
    streamInfo: WorkspaceStreamInfo
  ): Promise<void> {
    // Wait for any in-flight write to complete first (serialization)
    await this.awaitPendingPartialWrite(streamInfo);

    // Clear throttle timer
    if (streamInfo.partialWriteTimer) {
      clearTimeout(streamInfo.partialWriteTimer);
      streamInfo.partialWriteTimer = undefined;
    }

    // Start new write and track the promise
    streamInfo.partialWritePromise = (async () => {
      try {
        await this.historyService.writePartial(
          workspaceId as string,
          this.buildPartialAssistantMessage(streamInfo)
        );
        streamInfo.lastPartialWriteTime = Date.now();
      } catch (error) {
        log.error("Failed to write partial message:", error);
      } finally {
        // Clear promise when write completes
        streamInfo.partialWritePromise = undefined;
      }
    })();

    // Wait for this write to complete
    await streamInfo.partialWritePromise;
  }

  /**
   * Atomically ensures stream safety by cancelling any existing stream