feat(smoke): add compliance-smoke crate + scripts/smoke.sh tenant-gating harness

A minimal Axum binary that mounts compliance-core's M7.1 middleware on
three endpoints (public health, protected GET echo, protected POST echo)
so we can prove the tenant-gating contract end-to-end against a live KC
before any auth-path PR merges.

scripts/smoke.sh drives the binary against the five test users defined
in the certifai realm (admin/user → active, trial/frozen/archived) and
asserts the exact response code per (user × method × endpoint). Run it
once before touching auth, tenant_status, or org_roles code.

Validated locally — 15/15 assertions pass:
* anon/bogus → 401 on protected, 200 on /health
* active/trial → 200 on read + write
* frozen → 200 read, 402 write (read-after-cancel gate)
* archived → 410 read + 410 write (retention window closed)

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Cargo.toml

@@ -6,6 +6,7 @@ members = [
     "compliance-graph",
     "compliance-dast",
     "compliance-mcp",
+    "compliance-smoke",
 ]
 resolver = "2"