[Spike] Set up some general health monitoring in Datadog for requests, etc.

[ndouglas]

Description

@edmund-dunn and I have discussed the random issues recently. It'd be great to expand the logging/metrics capture we do so we can correlate any weird issues we encounter with other issues in the broader system.

• RDS - Slow Queries
• Tugboat Disk Storage Space (Relates to [tugboat] Disk space monitoring #10987 and Schedule and Document Tugboat Agent Cleanup Script and Monitor Free Disk Space #13095)

Acceptance Criteria

• We've identified a few ways in which our metrics/logging can be expanded for greater insight into the system.
• We've added this to a dashboard or some other system (see [SPIKE] Brainstorm a status.<env>.cms.va.gov solution. #14152 ) for ease of access during crises.

[BerniXiongA6]

Hi @ndouglas @edmund-dunn -- if we weren't able to get to this in S94, I can have us carry it over to S95. Lmk, thanks!

[ndouglas]

Yeah @BerniXiongA6 it should roll over to S95.