fix: json parse crashes in monitor model with safe parsing

[dharunashokkumar]

fixes json parse crashes when invalid json is stored in database for kafka and rabbitmq monitors.

added safe json parsing with fallback to default values instead of crashing.

[Copilot]

Pull request overview

This PR fixes crashes caused by invalid JSON in the database for Kafka and RabbitMQ monitor configurations by introducing safe JSON parsing with fallback to default values.

Changes:

• Added a safeJsonParse static method to handle JSON parsing errors gracefully
• Replaced all direct JSON.parse() calls for Kafka and RabbitMQ monitor fields with safe parsing
• Implemented error logging when JSON parsing fails

[Copilot]

Using null as the default value for conditions may be inconsistent with other fields that use empty arrays or objects. Consider using an empty array [] or empty object {} as the default depending on the expected data structure for conditions, to prevent potential null reference issues in code that consumes this field.

Suggested change

	conditions: Monitor.safeJsonParse(this.conditions, null, "conditions"),
	conditions: Monitor.safeJsonParse(this.conditions, [], "conditions"),

[CommanderStorm]

how did the invalid json end up in the db in the first place?

I think a better place to fix this is Monitor.validatte => fix it before we have garbage in the db

[CommanderStorm]

LGTM, thanks

[github-actions]

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