Add database connection retry logic on startup

[Aharshi3614]

Description

Currently, if MongoDB fails to connect on first attempt, the server crashes. Adding retry logic improves reliability.

Goals

• Retry MongoDB connection on failure
• Configurable retry count and delay
• Graceful failure after max retries

[github-actions]

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[github-actions]

The issue proposes adding retry logic for MongoDB connections during server startup to improve reliability. It suggests implementing configurable retry attempts and delay times, with the server gracefully failing after reaching the maximum retries if the connection is unsuccessful.