feat: Initialize Zastava Webhook service with TLS and Authority authentication

- Added Program.cs to set up the web application with Serilog for logging, health check endpoints, and a placeholder admission endpoint.
- Configured Kestrel server to use TLS 1.3 and handle client certificates appropriately.
- Created StellaOps.Zastava.Webhook.csproj with necessary dependencies including Serilog and Polly.
- Documented tasks in TASKS.md for the Zastava Webhook project, outlining current work and exit criteria for each task.

src/StellaOps.Excititor.Policy.Tests/VexPolicyProviderTests.cs

@@ -21,6 +21,9 @@ public sealed class VexPolicyProviderTests
 
         Assert.Equal(VexConsensusPolicyOptions.BaselineVersion, snapshot.Version);
         Assert.Empty(snapshot.Issues);
+        Assert.Equal(VexConsensusPolicyOptions.DefaultWeightCeiling, snapshot.ConsensusOptions.WeightCeiling);
+        Assert.Equal(VexConsensusPolicyOptions.DefaultAlpha, snapshot.ConsensusOptions.Alpha);
+        Assert.Equal(VexConsensusPolicyOptions.DefaultBeta, snapshot.ConsensusOptions.Beta);
 
         var evaluator = new VexPolicyEvaluator(provider);
         var consensusProvider = new VexProvider("vendor", "Vendor", VexProviderKind.Vendor);
@@ -63,6 +66,9 @@ public sealed class VexPolicyProviderTests
         Assert.Equal("custom/v1", snapshot.Version);
         Assert.NotEmpty(snapshot.Issues);
         Assert.Equal(0.95, snapshot.ConsensusOptions.ProviderOverrides["vendor"]);
+        Assert.Contains(snapshot.Issues, issue => issue.Code == "weights.vendor.range");
+        Assert.Equal(VexConsensusPolicyOptions.DefaultWeightCeiling, snapshot.ConsensusOptions.WeightCeiling);
+        Assert.Equal(1.0, snapshot.ConsensusOptions.VendorWeight);
 
         var evaluator = new VexPolicyEvaluator(provider);
         var vendor = new VexProvider("vendor", "Vendor", VexProviderKind.Vendor);