pricing: claude-haiku-4.5 unpriced in copilot store attribution ($0 vs billed)

[iamtoruk]

From kelchm's #946 validation (machine A): claude-haiku-4.5 store rows attribute $0 while GitHub billed $0.0063536 — the model is missing from the pricing path used for copilot store rows. Pre-existing gap, not a #946 defect. Fix: add/alias the rate.