pdpv0: audit pdp tasks for robust lifecycle management

[BigLep]

We need to audit our PDP tasks and make sure they all have appropriate:

• Priority
• Retries
• Fault detection w/ back-off and eventual termination with no chance of being re-run (requires more database state as per proving task fixes.

We did this for the pdpNotifier task as part of work to fix FilOzone/filecoin-services#380 but we now need to do it for the other pdp tasks.

TODO: @rvagg to fill in details more details here.

[BigLep]

2026-01-15 conversation: #871 will do a lot of this. It will handle what we do know is a problem; this issue is here to see if there is anything else we weren't handling properly.