Investigate adding trace level logging that helps identify tablets not compacting that need to

**Is your feature request related to a problem? Please describe.**

The overall problem is described in #4089.

**Describe the solution you'd like**

Is there trace level logging that could be added to the DefaultCompactionPlanner that would help identify specific configuration that is preventing a needed compaction? This trace level logging could be enabled after seeing a warning from the code added in #4089.

**Describe alternatives you've considered**

An alternative would be tool that a user could point at a tablet and it emits detailed information about what compaction actions it would or would not take for that tablet.

Start by reading issue #4089 and the DefaultCompactionPlanner implementation. Trace how a tablet's compaction decisions are made and identify which configuration prevents a needed compaction. Done means the investigation produces actionable trace-level diagnostics or a concrete determination that a separate tablet-inspection tool is needed.

Written by the indexing model from the issue text.