Add unit tests for PackRunAttestation and SealedInstallEnforcer

- Implement comprehensive tests for PackRunAttestationService, covering attestation generation, verification, and event emission.
- Add tests for SealedInstallEnforcer to validate sealed install requirements and enforcement logic.
- Introduce a MonacoLoaderService stub for testing purposes to prevent Monaco workers/styles from loading during Karma runs.

src/Concelier/__Libraries/StellaOps.Concelier.Storage.Postgres/StellaOps.Concelier.Storage.Postgres.csproj

@@ -14,9 +14,15 @@
     <EmbeddedResource Include="Migrations\**\*.sql" LogicalName="%(RecursiveDir)%(Filename)%(Extension)" />
   </ItemGroup>
 
+  <ItemGroup>
+    <!-- Exclude legacy Mongo-based import/conversion helpers until Postgres-native pipeline is ready -->
+    <Compile Remove="Converters\**\*.cs" />
+    <Compile Remove="Conversion\**\*.cs" />
+  </ItemGroup>
+
   <ItemGroup>
     <ProjectReference Include="..\..\..\__Libraries\StellaOps.Infrastructure.Postgres\StellaOps.Infrastructure.Postgres.csproj" />
     <ProjectReference Include="..\StellaOps.Concelier.Core\StellaOps.Concelier.Core.csproj" />
   </ItemGroup>
 
-</Project>
+</Project>