R1:2fb266de7c1a

Fix some of the most obvious bugs in fact generation from Maniphest tasks

Summary:
Depends on D19121. Ref T13083. Group transactions and show groups in the debugging view.

Fix some of the most obvious issues with fact generation:

- No more 0-point facts.
- Engine can now generate at least one of every type of fact.

Test Plan: Generated facts, viewed them in the debugging view, fact generation largely appeared to align with reality. No more "no facts in storage" facts.

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