docs: fix Event Receiver queue description in architecture overview (#280)

* Initial plan

* fix docs: correct Event Receiver queue type and size in architecture overview

Co-authored-by: shibu-kv <89052442+shibu-kv@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: shibu-kv <89052442+shibu-kv@users.noreply.github.com>

Author: Copilot

docs/architecture/overview.md

@@ -105,7 +105,7 @@ graph TB
 
 #### Event Receiver
 - **Purpose**: Queue and process incoming events
-- **Queue**: Lock-free ring buffer (1000 events)
+- **Queue**: Mutex/condition-variable-protected queue (200 events max, see `T2EVENTQUEUE_MAX_LIMIT`)
 - **Thread**: Dedicated event processing thread
 - **Files**: `source/bulkdata/t2eventreceiver.c`