feat: Implement IsolatedReplayContext for deterministic audit replay

- Added IsolatedReplayContext class to provide an isolated environment for replaying audit bundles without external calls.
- Introduced methods for initializing the context, verifying input digests, and extracting inputs for policy evaluation.
- Created supporting interfaces and options for context configuration.

feat: Create ReplayExecutor for executing policy re-evaluation and verdict comparison

- Developed ReplayExecutor class to handle the execution of replay processes, including input verification and verdict comparison.
- Implemented detailed drift detection and error handling during replay execution.
- Added interfaces for policy evaluation and replay execution options.

feat: Add ScanSnapshotFetcher for fetching scan data and snapshots

- Introduced ScanSnapshotFetcher class to retrieve necessary scan data and snapshots for audit bundle creation.
- Implemented methods to fetch scan metadata, advisory feeds, policy snapshots, and VEX statements.
- Created supporting interfaces for scan data, feed snapshots, and policy snapshots.

src/Cli/StellaOps.Cli/Commands/ReachabilityCommandGroup.cs

@@ -277,8 +277,8 @@ public static class ReachabilityCommandGroup
             if (verbose)
             {
                 Console.WriteLine($"  Format: {format}");
-                Console.WriteLine($"  Nodes: {subgraph.Nodes?.Count ?? 0}");
-                Console.WriteLine($"  Edges: {subgraph.Edges?.Count ?? 0}");
+                Console.WriteLine($"  Nodes: {subgraph.Nodes?.Length ?? 0}");
+                Console.WriteLine($"  Edges: {subgraph.Edges?.Length ?? 0}");
             }
 
             return 0;