Migrate Approvals interface patterns

docs/INTERFACE_PATTERN_MIGRATION.md

@@ -0,0 +1,30 @@
+# Approvals Interface Pattern Migration
+
+This migration applies the GovOPlaN interface pattern language to the
+Approvals-owned route without changing the append-only approval model or
+importing optional sibling modules.
+
+## Surface Inventory
+
+| Surface | Archetype | Consequence class | Contract |
+| --- | --- | --- | --- |
+| `/approvals` list | Searchable work queue | Select request or create immutable chain | Shared loading, empty, error, permission, selection, and help states |
+| Approval detail | Governed record detail | Inspect exact subject, chain, state, and evidence | Locale-aware history, status, provenance, explained lifecycle actions |
+| Request dialog | Consequential definition editor | Freeze exact subject and approval chain | Guarded draft, field help, validation reasons, at least one step |
+| Decision dialog | Governed decision | Append approval or rejection evidence | Required reason/signature, guarded draft, explicit confirmation action |
+
+## Consequence And Availability Rules
+
+- Creation freezes the subject identity and digest plus every ordered step,
+  selector, quorum, separation, and signature requirement.
+- Approving or rejecting appends attributable evidence and cannot be edited.
+- Only pending or escalated requests can be decided. Terminal requests remain
+  available for reconstruction.
+- Missing create or decide permission is visible and points to the Access role
+  assignment destination and responsible administrator.
+- Signature references are evidence pointers and never a cryptographic claim.
+
+The module uses Core dialogs, controls, status, blockers, help, loading, empty,
+error, and draft-guard contracts. Native selection buttons preserve keyboard
+order; bounded list/detail viewports remain responsive. English and German
+catalogues cover module-owned copy and dates follow the active platform locale.