[Fabric-Admin] Update the Fabric Sync guide to explain the confusion

Author: yufengwangca

docs/guides/fabric_synchronization_guide.md

@@ -118,6 +118,11 @@ of Ecosystem 1 has successfully paired with Ecosystem 2 on Endpoint 2:
 >>> A new device is added on Endpoint 2.
 ```
 
+Note: We only need to add the local bridge to the ecosystem to trigger the
+Fabric Sync Setup process. In the example above, the Fabric Sync Setup process
+is initiated by the command 'add-bridge' from Ecosystem 1. Adding the local
+bridge on the other side is optional.
+
 ### Pair Light Example to Ecosystem 2
 
 Since Fabric-Bridge also functions as a Matter server, running it alongside the

examples/fabric-admin/commands/interactive/InteractiveCommands.cpp

@@ -43,7 +43,7 @@ constexpr char kInteractiveModeHistoryFileName[] = "chip_tool_history";
 constexpr char kInteractiveModeStopCommand[]     = "quit()";
 
 #if defined(PW_RPC_ENABLED)
-constexpr uint16_t kRetryIntervalS = 5;
+constexpr uint16_t kRetryIntervalS = 3;
 #endif
 
 // File pointer for the log file