The DefaultServerMonitor fails with an ArithmeticException due to Math.toIntExact(serverSettings.getHeartbeatFrequency(MILLISECONDS)) exceeding integer limits. This is caused by missing validation in ServerSettings for heartbeatFrequency, allowing inputs higher than Integer.MAX_VALUE and preventing DefaultServerMonitor from sending a hello command.

Proposed Changes:

1. Implement integer validation in ServerSettings#heartbeatFrequency to check for values not exceeding Integer.MAX_VALUE similarly to SocketSettings.java#L288. 
2. Update the Javadoc for heartbeatFrequency to clearly state the integer value limitation, aligning with the documentation style in SocketSettings#readTimeout and connectTimeout.

Acceptance Criteria:

1. heartbeatFrequency in ServerSettings validates values to ensure they do not exceed Integer.MAX_VALUE.
2. The updated Javadoc accurately reflects the integer value limitation.
3. A test case confirms that an error is thrown when a long value exceeding Integer.MAX_VALUE is used.