Verification: Sending Library (Phase 1)

Bidirectional traceability between requirements and the Design §10 test catalog. Test implementations land in common-module/lib/src/test/kotlin/cards/arda/common/lib/infra/email/ (Kotest, MockEngine — see Testing Elements).

Requirement	Verified by	Level	Status
REQ-LIB-001	BV-4-03 (header hygiene, construction failure)	Unit	planned
REQ-LIB-002	BV-4-03 (fromHeader RFC 5322 pin)	Unit	planned
REQ-LIB-003	BV-3-01 (validation, toString redaction)	Unit	planned
REQ-LIB-004	BV-3-02 (config-bound wiring)	Unit	planned
REQ-LIB-005	BV-4-01 (outcome classification)	Unit	planned
REQ-LIB-006	BV-4-02 (retry/backoff, short-circuit), BV-7-02 (transport exhaustion)	Unit	planned
REQ-LIB-007	BV-4-04 (wire-format golden pin)	Unit	planned
REQ-LIB-008	BV-4-02 (hook invocation per outcome)	Unit	planned
REQ-LIB-009	BV-2-01 (absent/malformed/valid binding)	Unit	planned
REQ-LIB-010	BV-2-02 (field semantics, defaults)	Unit	planned
REQ-LIB-011	kotlin-coding review pass over all new lines + Kover gate (≥67% instruction / 73% line)	Review / gate	planned

Downstream (not this phase): BV-3-03 and BV-4-05 verify the operations adoption in Phase 3; BV-4-06 executes at the Phase 4 dev gate.