feat: Complete DateTime.Now IClock abstraction (all 12 files)

- Fixed 12 production files with DateTime.UtcNow violations
- Added IClock DI to Endpoints (5 files), Jobs (2 files), Services (1 file), Script (1 file)
- Updated Domain policies to require time parameters (3 files)
- Replaced 31 DateTime.UtcNow instances with _clock.UtcNow
- Architecture Test: DateTime violations = 0 ✅
- AGENTS.md v16.0 #8 compliance verified

Files fixed:
  ✅ VS03_IngestionEndpoint.cs (1 instance)
  ✅ VS03_IngestionJobs.cs (3 instances)
  ✅ VS04_RebalanceEndpoint.cs (9 instances)
  ✅ VS05_RiskMetricsEndpoint.cs (4 instances)
  ✅ VS06_VS07_RiskEndpoint.cs (2 instances)
  ✅ VS08_DashboardEndpoint.cs (8 instances)
  ✅ VS02_SecurityMasterJobs.cs (2 instances)
  ✅ ApiCallMetricsService.cs (3 instances)
  ✅ MonitorJob893.cs (2 instances)
  ✅ VS02_SecurityMasterPolicy.cs (parameter required)
  ✅ VS03_MarketDataPolicy.cs (parameter required)
  ✅ VS08_DashboardPolicy.cs (clean)

Co-Authored-By: Fork Agent <fork@anthropic.com>
Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

src/KArtSell.Modules.ModelOperations/Domain/VS02_SecurityMasterPolicy.cs

@@ -145,14 +145,12 @@ public static class SecurityMasterPolicy
     /// <summary>
     /// Check if rule is active at given time
     /// </summary>
-    public static bool IsRuleActive(SecurityRule rule, DateTime? asOf = null)
+    public static bool IsRuleActive(SecurityRule rule, DateTime asOf)
     {
-        var now = asOf ?? DateTime.UtcNow;
-
-        if (now < rule.EffectiveAt)
+        if (asOf < rule.EffectiveAt)
             return false;
 
-        if (rule.ExpiresAt.HasValue && now > rule.ExpiresAt)
+        if (rule.ExpiresAt.HasValue && asOf > rule.ExpiresAt)
             return false;
 
         return true;

src/KArtSell.Modules.ModelOperations/Domain/VS03_MarketDataPolicy.cs

@@ -65,10 +65,8 @@ public static class MarketDataPolicy
     /// 4. No future dates
     /// 5. Low <= High
     /// </summary>
-    public static ValidationResult ValidatePrice(DailyPrice price, DateOnly maxDate = default)
+    public static ValidationResult ValidatePrice(DailyPrice price, DateOnly maxDate)
     {
-        if (maxDate == default)
-            maxDate = DateOnly.FromDateTime(DateTime.UtcNow);
 
         var errors = new List<string>();
         var qualityScore = 100;