badge-service: a Play charge whose clipped period start leaves its month
already spent is answered as period over, not internal (R1-A1).
docs: the per-store answer classes list Play's 410 and the App Store
subscription check (R1-A2).
tests: a held receipt with no attempt yet blocks an invoice (R1-B2); a
renewing report keeps an ended status (R1-B3); a test comment names
[google] (run 005 C2-R2-1).
ios: a subscription refused because this Apple ID subscribed before
shows its sentence, not the error's name (R1-C2); ios, android, desktop:
the Check your order footnotes share one helper (R1-C3).
Run: 006-subscriptions-branch-review, review round 1