PR #479 — Milestone 2: Activity Records & Reward Computation Infrastructure

Parent: #581 PR: https://github.com/canton-foundation/canton-dev-fund/pull/479

| | | | :---- | :---- | | Estimated Delivery | Month 4 | | Focus | Precise activity record computation, three-stage reward computation, and Scan API endpoints |

Deliverables:

• Scan app: ScanTcsStore temporal contract store for FeaturedAppRight, OpenMiningRound, and AmuletRules with as-of-round-start lookups.
• Scan app: ScanTcsIngestion service feeding the temporal store from the Ledger API.
• Scan app: extended ScanVerdictIngestion computing activity records per CIP-0104 formula, with round attribution and confirmer-based traffic weight computation.
• Scan app: ComputeAppRewardsTrigger implementing the three-stage computation (activity totals → reward totals → Merkle-tree hashes).
• Unit tests validating SQL computations match Scala and Daml decimal computations.
• Activity records served via /v2/events on Scan.

Acceptance Criteria: Precise per-party activity records and reward computations are available on the Scan API for closed mining rounds.