test(sag): cover audit event export lifecycle

[gregkonush]

Summary

• Added a SAG gateway regression test for audit event JSONL export.
• Covers the mutating task lifecycle from intake and plan through connector execution, approval request, and approval.
• Verifies exported audit events remain replayable with stable request hashes and task-scoped correlation IDs.

Related Issues

None

Testing

• bun install failed because tree-sitter-json postinstall could not load env-paths from node-gyp.
• bun install --ignore-scripts
• bun run --filter @proompteng/sag test -- src/server/gateway.test.ts
• bun run --filter @proompteng/sag format:check
• bun run --filter @proompteng/sag tsc
• bun run --filter @proompteng/sag lint:oxlint

Screenshots (if applicable)

N/A

Breaking Changes

None

Checklist

• Testing section documents the exact validation performed (or N/A with justification).
• Screenshots and Breaking Changes sections are handled appropriately (removed or filled in).
• Documentation, release notes, and follow-ups are updated or tracked.

[gregkonush]

Status: PR opened, local validation complete, and CI green.

• Branch: codex/sag-mp58yb71
• Commit: cec527197 test(sag): cover audit event export lifecycle
• Change: added a SAG audit JSONL export lifecycle regression test.
• Local checks: targeted SAG Vitest, format check, TypeScript check, and oxlint all passed.
• CI: GitHub checks passing; PR is mergeable and clean.