Add comprehensive tests for PathConfidenceScorer, PathEnumerator, ShellSymbolicExecutor, and SymbolicState

- Implemented unit tests for PathConfidenceScorer to evaluate path scoring under various conditions, including empty constraints, known and unknown constraints, environmental dependencies, and custom weights.
- Developed tests for PathEnumerator to ensure correct path enumeration from simple scripts, handling known environments, and respecting maximum paths and depth limits.
- Created tests for ShellSymbolicExecutor to validate execution of shell scripts, including handling of commands, branching, and environment tracking.
- Added tests for SymbolicState to verify state management, variable handling, constraint addition, and environment dependency collection.

src/Graph/__Tests/StellaOps.Graph.Api.Tests/AuditLoggerTests.cs

@@ -25,6 +25,8 @@ public class AuditLoggerTests
 
         var recent = logger.GetRecent();
         Assert.True(recent.Count <= 100);
-        Assert.Equal(509, recent.First().Timestamp.Minute);
+        // First entry is the most recent (minute 509). Verify using total minutes from epoch.
+        var minutesFromEpoch = (int)(recent.First().Timestamp - DateTimeOffset.UnixEpoch).TotalMinutes;
+        Assert.Equal(509, minutesFromEpoch);
     }
 }