perf(postgres): stream compliance projection children

[jonathanhaaswriter]

Summary

• omit normalized occurrence and milestone arrays from current JSONB only while loading detail projections
• decode immutable revision, occurrence, and action rows as SQL rows arrive instead of buffering raw JSON bodies
• preserve tenant and parent predicates, ordering, stored records, list behavior, and response shape

Validation

• go test ./internal/statestore/postgres -count=1
• go test ./internal/complianceremediation -count=1
• go test ./internal/bootstrap -run Compliance(Remediation|Work)|GRC -count=1
• go test -race ./internal/statestore/postgres -run focused compliance tests -count=1
• make check-structural check-structural-test check-arch
• BenchmarkComplianceWorkItemOccurrenceReadMaterialization: 759783 to 474256 B/op; 9003 to 5409 allocs/op

Full local make verify stopped before Cargo execution at the managed capacity gate; hosted required checks remain authoritative.