feat: Add UI benchmark driver and scenarios for graph interactions

- Introduced `ui_bench_driver.mjs` to read scenarios and fixture manifest, generating a deterministic run plan.
- Created `ui_bench_plan.md` outlining the purpose, scope, and next steps for the benchmark.
- Added `ui_bench_scenarios.json` containing various scenarios for graph UI interactions.
- Implemented tests for CLI commands, ensuring bundle verification and telemetry defaults.
- Developed schemas for orchestrator components, including replay manifests and event envelopes.
- Added mock API for risk management, including listing and statistics functionalities.
- Implemented models for risk profiles and query options to support the new API.

docs/modules/signals/decay/confidence_decay_config.yaml

@@ -0,0 +1,41 @@
+version: 1
+updated_at: 2025-12-01T00:00:00Z
+entities:
+  vulnerability:
+    tau_days: 21
+    tau_min: 7
+    tau_max: 90
+    confidence_floor:
+      critical: 0.60
+      high: 0.45
+      medium: 0.30
+      low: 0.20
+    sla_floor:
+      critical: 0.60
+      high: 0.50
+    freeze_default_days: 30
+  incident:
+    tau_days: 14
+    tau_min: 3
+    tau_max: 60
+signals_taxonomy:
+  exploit: 1.0
+  customer_incident: 0.9
+  threat_intel: 0.7
+  code_change: 0.4
+  artifact_refresh: 0.3
+  metadata_touch: 0.1
+time:
+  reject_future_minutes: 5
+  reject_backdated_days: 30
+recompute:
+  schedule_utc: "03:00"
+  snapshot_retention_days: 30
+observability:
+  alerts:
+    missing_snapshot_hours: 26
+    sla_floor_breach: true
+    uncertainty_band_force: 0.4
+signing:
+  predicate: stella.ops/confidenceDecayConfig@v1
+  dsse_required: true