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/cli/contracts/cli-spec-v1.yaml

@@ -0,0 +1,63 @@
+version: 1
+generated: 2025-12-01T00:00:00Z
+compatibility:
+  policy: "SemVer-like: commands/flags/exitCodes are backwards compatible within major version."
+  deprecation:
+    noticeMinimumDays: 90
+    channels:
+      - release-notes
+      - --compat-report
+commands:
+  - name: advise
+    subcommands:
+      - name: summarize
+        formats: [json, markdown, table]
+        exitCodes:
+          0: success
+          2: validation-error
+          3: backend-unavailable
+      - name: explain
+        formats: [json, markdown, table]
+        exitCodes:
+          0: success
+          2: validation-error
+          3: backend-unavailable
+      - name: remediate
+        flags:
+          - name: strategy
+            required: false
+            values: [minimal, defense-in-depth, fast-track]
+        exitCodes:
+          0: success
+          2: validation-error
+          3: backend-unavailable
+  - name: auth
+    subcommands:
+      - name: doctor
+        exitCodes:
+          0: success
+          4: auth-misconfigured
+          5: token-invalid
+telemetry:
+  defaultEnabled: false
+  envVars:
+    optIn: STELLAOPS_TELEMETRY=1
+    optOut: STELLAOPS_TELEMETRY=0
+  persistField: telemetryEnabled
+install:
+  checksumRequired: true
+  cosignVerifyDefault: true
+  exitCodes:
+    21: checksum-file-missing
+    22: checksum-mismatch
+buildxPlugin:
+  imageDigest: "sha256:0000000000000000000000000000000000000000000000000000000000000000"
+  rollbackCommand: "stella tool buildx rollback --to <digest>"
+determinism:
+  locale: "en-US"
+  timezone: "UTC"
+  jsonFormatting: "stable-sort-keys"
+  tableWidth: 80
+tests:
+  - name: cli-compatibility-regression
+    description: "Ensure commands/flags/exit codes match spec and telemetry defaults are enforced."