Stellar Index v0.5.0-rc.127

[v0.5.0-rc.127] — 2026-06-19

Added

• Per-hour trade_count on the source sparkline. /v1/sources?include=sparkline
  buckets now carry trade_count alongside volume_usd (the count was already
  computed in GetSourceVolumeHistory24h, just dropped on serialization).
  Powers the source page's new activity chart — trade-count line over USD-volume
  bars — replacing the flat volume-by-hour sparkline. Additive + backward-compatible.