feat: add Phase 4 x402 metering and Phase 5 hardening
Phase 4: Usage metrics service (container stats, post count, storage),
billing calculator with pro-rated monthly pricing, usage + payment
routes, x402 middleware wired to provisioning endpoint.
Phase 5: In-memory rate limiter (general 10/min + provision 2/hour),
admin routes (force teardown, suspend/resume), Dockerfile hardened
with non-root user and healthcheck. Suspended instance status added.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Jeff Emmett
a536a9bc0f