Feature/mongo pool config

[Lkomarek]

• Please check if the PR fulfills these requirements

• [x ] The commit message describes your change
• Tests for the changes have been added if possible (for bug fixes / features)
• [ x] Docs have been added / updated (for bug fixes / features)
• [x ] Changes are mentioned in the changelog (for bug fixes / features)

• What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)

Feature enhancement

• What is the current behavior? (You can also link to an open issue here)

The MongoDB client configuration does not expose connection pool settings. Users cannot configure the minimum/maximum pool size or the maximum idle time for pooled connections. Additionally, the MongoDB client does not set an application name identifier.

• What is the new behavior (if this is a feature change)?

The MongoDB client now supports three new configuration properties for connection pool management:
mongodb.maxConnectionIdleTime - controls how long idle connections remain in the pool (default: 600000ms / 10 minutes)
mongodb.minPoolSize - sets the minimum number of connections in the pool (default: 10)
mongodb.maxPoolSize - sets the maximum number of connections in the pool (default: 100)

The MongoDB client also now sets the application name for better monitoring and debugging.

• Does this PR introduce a breaking change? (What changes might users need to make in their setup due to this PR?)

No. All new configuration properties have sensible defaults and are backward compatible. Existing configurations will continue to work without any changes.

• Other information: