refactor(dotnet): centralize runtime audit trail

src/dotnet/QuantEngine.Application/Services/FactorComputationService.cs

@@ -1,6 +1,7 @@
 using System.Text.Json;
 using QuantEngine.Core.Domain;
 using QuantEngine.Core.Interfaces;
+using QuantEngine.Application.Interfaces;
 
 namespace QuantEngine.Application.Services;
 
@@ -15,34 +16,12 @@ public sealed record FactorComputationAudit(
 public sealed class FactorComputationService
 {
     private readonly HistoryIngestionService _history;
-    private readonly string _auditRoot;
+    private readonly IRuntimeAuditTrailService _auditTrail;
 
-    public FactorComputationService(HistoryIngestionService history)
+    public FactorComputationService(HistoryIngestionService history, IRuntimeAuditTrailService auditTrail)
     {
         _history = history;
-        _auditRoot = FindRepoTempRoot();
-    }
-
-    private static string FindRepoTempRoot()
-    {
-        var current = new DirectoryInfo(AppContext.BaseDirectory);
-        while (current != null)
-        {
-            if (Directory.Exists(Path.Combine(current.FullName, ".git")))
-            {
-                return Path.Combine(current.FullName, "Temp", "factor_audit");
-            }
-            current = current.Parent;
-        }
-
-        return Path.Combine(Directory.GetCurrentDirectory(), "Temp", "factor_audit");
-    }
-
-    private void AppendAudit(FactorComputationAudit audit)
-    {
-        Directory.CreateDirectory(_auditRoot);
-        var path = Path.Combine(_auditRoot, $"{audit.Ticker}.jsonl");
-        File.AppendAllText(path, JsonSerializer.Serialize(audit, new JsonSerializerOptions { WriteIndented = false }) + Environment.NewLine);
+        _auditTrail = auditTrail;
     }
 
     public FactorOutputs Compute(
@@ -53,7 +32,7 @@ public sealed class FactorComputationService
     {
         var computedAt = DateTimeOffset.UtcNow;
         var outputs = FactorCalculator.CalculateFactors(stockBars, indexBars);
-        AppendAudit(new FactorComputationAudit(ticker, stockBars.Count, indexBars.Count, "SUCCEEDED", computedAt, sourceVersion));
+        _auditTrail.Append("factor_audit", ticker, new FactorComputationAudit(ticker, stockBars.Count, indexBars.Count, "SUCCEEDED", computedAt, sourceVersion));
         return outputs;
     }
 
@@ -71,6 +50,6 @@ public sealed class FactorComputationService
         await _history.AppendFactorOutputAsync("stdev_20d", sourceVersion, outputs.StDev20D, "PASS", sourceVersion, when);
         await _history.AppendFactorOutputAsync("beta_60d", sourceVersion, outputs.Beta60D, "PASS", sourceVersion, when);
         await _history.AppendFactorOutputAsync("rs_20d", sourceVersion, outputs.Rs20D, "PASS", sourceVersion, when);
-        AppendAudit(new FactorComputationAudit(ticker, 0, 0, "PERSISTED", when, sourceVersion));
+        _auditTrail.Append("factor_audit", ticker, new FactorComputationAudit(ticker, 0, 0, "PERSISTED", when, sourceVersion));
     }
 }