Initial commit: VMware vSphere API simulator scaffold.

Add the FastAPI app, PostgreSQL migrations, Docker/Helm packaging, API
contracts, docs, client examples, and the unit/integration/compatibility
test suite for local client and tooling labs without a real vCenter.

tests/unit/test_vsphere_compatibility.py

@@ -0,0 +1,27 @@
+"""vSphere Implementation coverage payload tests."""
+
+from app.vsphere.contracts.compatibility import evidence_ledger, vsphere_compatibility_payload
+from app.vsphere.contracts.matrix import VERSIONS, catalog_entries_for_major
+from app.vsphere.rest.coverage import catalog_entries
+
+
+def test_compatibility_payload_matches_matrix() -> None:
+    universe = len(catalog_entries())
+    for major in VERSIONS:
+        payload = vsphere_compatibility_payload(major)
+        implemented = len(catalog_entries_for_major(major))
+        assert payload["total_declared"] == universe
+        assert payload["levels"]["implemented"]["count"] == implemented
+        assert payload["levels"]["declared"]["count"] == universe
+        assert payload["levels"]["gated"]["count"] == universe - implemented
+        assert payload["levels"]["schema_only"]["count"] == universe - implemented
+        assert payload["summary"]["coverage"] == round(implemented / universe, 4)
+        assert payload["summary"]["universe_by_verb"]
+        assert "GET" in payload["summary"]["by_verb"] or implemented == 0
+
+
+def test_evidence_ledger_includes_levels() -> None:
+    ledger = evidence_ledger(9)
+    assert ledger["summary"]["implemented_methods"] == len(catalog_entries())
+    assert ledger["summary"]["coverage"] == 1.0
+    assert ledger["levels"]["implemented"]["count"] == ledger["summary"]["universe_methods"]