feat: Implement Policy Engine Evaluation Service and Cache with unit tests

Temp commit to debug

etc/findings-ledger.yaml

@@ -3,3 +3,25 @@ findings:
   ledger:
     database:
       connectionString: Host=postgres
+    authority:
+      issuer: https://authority.internal/
+      requireHttpsMetadata: true
+      metadataAddress: https://authority.internal/.well-known/openid-configuration
+      audiences:
+        - stellaops:vuln-ledger
+      requiredScopes:
+        - vuln:operate
+        - vuln:audit
+    merkle:
+      batchSize: 1000
+      windowDuration: 00:15:00
+    projection:
+      batchSize: 200
+      idleDelay: 00:00:05
+    policyEngine:
+      baseAddress: https://policy-engine.svc.cluster.local/api/
+      tenantHeaderName: X-Stella-Tenant
+      requestTimeout: 00:00:10
+      cache:
+        sizeLimit: 2048
+        entryLifetime: 00:30:00