feat: implement F3 CLI to list power table and proportional power at …

…instance (#12698)

* Implement F3 CLI to list power table and proportional power at instance

Implement utility CLIs to:
* get the power table used by F3 at a given instance ID.
* get total proportional power of a list of actors at a given instance
  ID.

These utilities allow us to debug the exact participation power for an
instance without having to manually calculate it or estimate it from
the latest power.

* Update changelog

* Address lint issue

* Regenerate CLI docs

* Take instance ID via flag and actor IDs as args

* Reduce indentation by defiling top level vars

* Work around bug in docsgencli by using one-liner usage

CHANGELOG.md

@@ -6,6 +6,10 @@
 
 - Make `EthTraceFilter` / `trace_filter` skip null rounds instead of erroring. ([filecoin-project/lotus#12702](https://github.com/filecoin-project/lotus/pull/12702))
 
+## New Features
+
+* Implement F3 utility CLIs to list the power table for a given instance and sum the proportional power of a set of actors that participate in a given instance. See: https://github.com/filecoin-project/lotus/pull/12698.
+
 # UNRELEASED v1.31.0
 
 See https://github.com/filecoin-project/lotus/blob/release/v1.31.0/CHANGELOG.md