feat: add bounded workflow execution measurement

docs/reports/data/phase-6-workflow-load/environment.json

@@ -0,0 +1,40 @@
+{
+  "date_local": "2026-09-20",
+  "timezone": "Asia/Shanghai",
+  "test_go": "go1.25.14",
+  "declared_go": "1.27.1",
+  "temporary_modfile": true,
+  "mysql": "8.4.10",
+  "docker_vm_cpus": 12,
+  "docker_vm_memory_bytes": 12529274880,
+  "architecture": "arm64",
+  "orbit_processes": 1,
+  "mysql_nodes": 1,
+  "worker_processes": 1,
+  "worker_connections_normal": 2,
+  "worker_capacity_each": 4,
+  "workflow_requests": 24,
+  "workflow_concurrency": 6,
+  "queue_max_concurrency": 4,
+  "queue_rate_per_second": 10,
+  "poll_interval_ms": 100,
+  "http_timeout_ms": 5000,
+  "run_timeout_ms": 90000,
+  "metrics_enabled": false,
+  "cpu_memory_limits": "No dedicated limits; shared local Docker VM, other workloads possible",
+  "fresh_disposable_database": true,
+  "network": "Go runner shares MySQL container network namespace; loopback HTTP/WSS and MySQL",
+  "schema_verification": {
+    "schema_version": 28,
+    "migration_count": 28,
+    "foreign_key_count": 0,
+    "required_index_count": 6,
+    "complete": true
+  },
+  "source_sha256": {
+    "sdk/go/cmd/orbit-workflow-load/main.go": "05a160431b26d91ab430392b23f4fcf76bd23dfeb21bd2047fe8372c17e93fe5",
+    "sdk/go/cmd/orbit-workflow-load/measure.go": "1a31d06d3a9e483aee5aca115f7f1230649e050a0bddae1770659fe2735a99a3",
+    "sdk/go/cmd/orbit-workflow-load/measure_test.go": "42e710139f515aa339b5684107d00fcb413688e7512fc4c36ebfe56776ad41a1",
+    "sdk/go/cmd/orbit-workflow-load/report.go": "701a27a3f4f56cf9566fbcf97fba8024ced36b32754f4a5dcdae4646a2a4b24a"
+  }
+}