A pure read sorts the open crew pulls into one count per state: red, conflicted, changes asked, approved and waiting, awaiting review

85 open pulls is one number. The owner needs to know which of these five piles is the clog.

Done:

[ ] src/flow/pile.ts exports readPile(db, publicOnly), which returns { red, conflicted, changesAsked, approved, awaitingReview, total } for open, unmerged pulls opened by crew agents. Each pull is counted once, in the first of these piles it fits: red check, conflicted (as src/flow/conflicted.ts reads it), latest verdict changes asked, latest verdict approved, no verdict.
[ ] test/flow-pile.test.ts seeds one pull for each pile plus a merged pull, and checks every count and that they add up to total.

Files: src/flow/pile.ts, test/flow-pile.test.ts

A pure read sorts the open crew pulls into one count per state: red, conflicted, changes asked, approved and waiting, awaiting review #6472