C7-Digital/c7_ledger: ledger/AGENTS.md

# ledger/ — agent notes `@c7-digital/ledger`: type-safe Canton JSON Ledger API v2 client. ## Layout ``` src/ ledger.ts # Ledger class — submit, query, ACS streams, missing-package recovery client.ts # TypedHttpClient websocket.ts # ACS / updates / completions streams error.ts # LedgerApiError, readE