Cleanup compaction tmp files in upgrade from 2.1 to 4.0

[keith-turner]

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

The naming format for compaction tmp files is very different between 2.1 and 4.0. Any compaction tmp files left from 2.1 during upgrade would never be used. Does not seem any 4.0 code would every clean up these 2.1 tmp files.

Describe the solution you'd like

During 4.0 upgrade look for 2.1 compaction tmp files in each volume and remove them.

[keith-turner]

While doing some debugging noticed that 4.0 flush tmp files may look like 2.1 tmp files. Maybe the cleanup in upgrade could exclude flush files to be conservative.

2026-04-02T16:06:25,922 Thread[134;Minor compacting 1;r:0580;r:0560] [tablet.files] DEBUG: 1;r:0580;r:0560 renamed F000005b.rf_tmp to F000005b.rf