Initial commit: Financial Crime domain exemplar

financial_crime/entities/payer.md

@@ -0,0 +1,47 @@
+# [Financial Crime](../domain.md)
+
+## Entities
+
+### Payer
+
+A Payer is a Party Role representing the party from whom funds are debited in a transaction.
+
+```mermaid
+---
+config:
+  layout: elk
+---
+classDiagram
+  class Payer{
+    * Payer Identifier : string
+    Funding Source Reference : string
+  }
+
+  Payer --|> PartyRole
+
+  class PartyRole["<a href='https://github.com/Semprini/md-ddl/blob/main/examples/Financial%20Crime/entities/party_role.md'>Party Role</a>"]
+```
+
+```yaml
+extends: Party Role
+existence: independent
+mutability: slowly_changing
+attributes:
+  Payer Identifier:
+    type: string
+    identifier: primary
+    description: Unique identifier for the payer role instance.
+
+  Funding Source Reference:
+    type: string
+    description: Reference to the source account or instrument used to fund payments.
+```
+
+```yaml
+governance:
+  retention_basis: Inherited from domain default retention of 10 years post relationship end for AML/CTF record-keeping
+```
+
+## Relationships
+
+No relationships are sourced directly from Payer. The canonical direction is Transaction-owned — see [Transaction Has Debtor](transaction.md#transaction-has-debtor).