Local holder for Xochi Mandate envelopes.

Stores signed envelopes the local node can present (when this raxol is the agent operator) or has issued (when this raxol is the Member). Has no consume semantics -- Xochi's server enforces per-envelope budgets in its own KV. The Store is a pure holder + indexer.

Pattern

A GenServer owns writes; reads bypass through ETS directly with read_concurrency: true.

ETS table names are derived from the GenServer's registered name, so multiple Store instances can coexist on one node by passing a distinct :name to start_link/1:

{:ok, _} = Store.start_link(name: :buyer_mandates)
{:ok, _} = Store.start_link(name: :seller_mandates)
:ok = Store.put(envelope, :buyer_mandates)
mandates = Store.list_for_agent("0x...", :seller_mandates)

When :name is omitted, the Store registers as Raxol.Payments.Mandate.Store (the singleton default).

Primary key: envelope_hash (32-byte binary). Secondary indices:

• :agent_wallet (bag) -- "which envelopes can this agent present?"
• :human_wallet (bag) -- "which mandates have I issued?"

Optional DETS

Per-instance DETS persistence via the :dets_path option:

{:ok, _} = Store.start_link(name: :my_store, dets_path: "/var/lib/raxol/my.dets")

For the singleton case, :mandate_store_path in Application config still works as a global default:

config :raxol_payments, mandate_store_path: "/var/lib/raxol_payments/mandates.dets"

An explicit :dets_path opt always wins over the Application config. When neither is set, the Store is in-memory only.