Add Policy DSL Validator, Schema Exporter, and Simulation Smoke tools

- Implemented PolicyDslValidator with command-line options for strict mode and JSON output.
- Created PolicySchemaExporter to generate JSON schemas for policy-related models.
- Developed PolicySimulationSmoke tool to validate policy simulations against expected outcomes.
- Added project files and necessary dependencies for each tool.
- Ensured proper error handling and usage instructions across tools.

samples/policy/simulations/internal-only/diff.json

@@ -0,0 +1,23 @@
+{
+  "summary": {
+    "policy": "internal-only",
+    "policyDigest": "sha256:simulation-internal-only",
+    "changed": 2
+  },
+  "diffs": [
+    {
+      "findingId": "library:pkg/internal-app@2.0.0",
+      "baselineStatus": "Pass",
+      "projectedStatus": "RequiresVex",
+      "rule": "accept_vendor_vex",
+      "notes": "Trust vendor VEX statements for internal scope."
+    },
+    {
+      "findingId": "library:pkg/kev-component@3.1.4",
+      "baselineStatus": "Pass",
+      "projectedStatus": "RequiresVex",
+      "rule": "accept_vendor_vex",
+      "notes": "Trust vendor VEX statements for internal scope."
+    }
+  ]
+}