Verification: Phase 5 — API Proxy Update

Traceability Matrix

Requirement	Test	Type	Status
REQ-P5-001	T-P5-001: CompositeRenderResult type compiles and matches backend shape	Unit	Pending
REQ-P5-001	T-P5-002: GroupRenderResult includes optional debugPayload	Unit	Pending
REQ-P5-002	T-P5-003: ItemProxy.printLabels returns CompositeRenderResult	Unit	Pending
REQ-P5-002	T-P5-004: ItemProxy.printBreadcrumbs returns CompositeRenderResult	Unit	Pending
REQ-P5-002	T-P5-005: KanbanProxy.printCards returns CompositeRenderResult	Unit	Pending
REQ-P5-003	T-P5-006: printLabels with debug=true sends query parameter	Unit	Pending
REQ-P5-003	T-P5-007: printLabels with dryRun=true sends query parameter	Unit	Pending
REQ-P5-004	T-P5-008: KanbanProxy.unmarkPrinted calls correct endpoint	Unit	Pending
REQ-P5-005	T-P5-009: All existing proxy tests still pass	Unit	Pending
REQ-P5-006	T-P5-010: CHANGELOG updated	Review	Pending