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.

src/Bench/StellaOps.Bench/Graph/ui_bench_plan.md

@@ -0,0 +1,30 @@
+# Graph UI Bench Plan (BENCH-GRAPH-21-002)
+
+Purpose: provide a deterministic, headless flow for measuring graph UI interactions over large fixtures (50k/100k nodes).
+
+## Scope
+- Use synthetic fixtures under `samples/graph/interim/` until canonical SAMPLES-GRAPH-24-003 lands.
+- Drive a deterministic sequence of interactions:
+  1) Load graph canvas with specified fixture.
+  2) Pan to node `pkg-000001`.
+  3) Zoom in 2×, zoom out 1×.
+  4) Apply filter `name contains "package-0001"`.
+  5) Select node, expand neighbors (depth 1), collapse.
+  6) Toggle overlay layer (once available).
+- Capture timings: initial render, filter apply, expand/collapse, overlay toggle.
+
+## Determinism rules
+- Fixed seed for any randomized layouts (seed `424242`).
+- Disable animations/transitions where possible; otherwise measure after `requestAnimationFrame` settle.
+- No network calls; fixtures loaded from local file served by test harness.
+- Stable viewport (width=1280, height=720), device scale factor 1.
+
+## Artifacts
+- `ui_bench_scenarios.json` — canonical scenario list with step ids and notes.
+- `ui_bench_driver.mjs` — helper that reads scenario + fixture manifest and emits a run plan (no browser dependency). Intended to be wrapped by a Playwright script later.
+- Results format (proposed): NDJSON with `{stepId, name, durationMs, fixture, timestamp}`.
+
+## Next steps
+- Bind `ui_bench_driver.mjs` into a Playwright harness when Graph UI build/serve target is available.
+- Swap fixtures to SAMPLES-GRAPH-24-003 + overlay once schema finalized; keep scenario ids stable.
+- Add CI slice to run the driver and validate scenario/fixture bindings (no browser) to keep determinism checked in commits.