Reconciler does not correctly handle UNSAT resolutions

[joelanford]

Related to operator-framework/deppy#139 and possibly #329

In Reconcile we:

1. Check to see if Solve returned an error.
   • This currently can happen if a variable source returns an error when getting variables.
   • Notably, solve does NOT return an error for UNSAT. This error means "was not able to get variables or setup the solver"
2. Look for the matching variable in the solution

We skip the step of checking if the solution was SAT or UNSAT. UNSAT currently manifests as an error looking up the bundle entity from the solution. This "works", but it means users don't see the UNSAT reason that comes from solution.Error()

We should check solution.Error(), and handle it accordingly.

[joelanford]

This problem is pretty much solved by operator-framework/deppy#140, which is not yet in a release. We should ask deppy maintainers to create a release with this fix and then our op-con update will be pretty straightforward.