Add detailed ride diagnostics to match logging

server/src/Vanguard.Server/Matches/MatchGrain.cs

@@ -109,6 +109,14 @@ public sealed class MatchGrain : IMatchGrain
 
         _engine.Start(setup.FirstPlayer);
         RefreshSummary();
+
+        _logger.LogInformation(
+            "Match {MatchId}: created {Seat0} vs {Seat1}, first={FirstPlayer}. {State}",
+            _matchId,
+            _seats[0].PlayerId,
+            _seats[1].PlayerId,
+            setup.FirstPlayer,
+            DescribeTurnState());
     }
 
     public string MatchId => _matchId;
@@ -172,8 +180,8 @@ public sealed class MatchGrain : IMatchGrain
             await SendClockAsync(seat, now);
 
             _logger.LogInformation(
-                "Match {MatchId}: seat {Seat} attached (resume from {Seq}, now {Now}).",
-                _matchId, seat, resumeFromSeq, to);
+                "Match {MatchId}: seat {Seat} attached (resume from {Seq}, now {Now}). {State}",
+                _matchId, seat, resumeFromSeq, to, DescribeTurnState());
 
             await PersistHeaderAsync();
 
@@ -314,6 +322,10 @@ public sealed class MatchGrain : IMatchGrain
 
             var decisionBefore = _engine.State.ActivePlayer;
 
+            _logger.LogInformation(
+                "Match {MatchId}: seat {Seat} intent {IntentType} ({IntentId}) received. {State}",
+                _matchId, seat, DescribeIntent(intent.Intent), intentId, DescribeTurnState());
+
             CommandResult result;
             var commandText = string.Empty;
 
@@ -349,6 +361,20 @@ public sealed class MatchGrain : IMatchGrain
             await SendResultAsync(
                 seat, intentId, record.Accepted, record.Code, record.Reason, record.EventSeq, duplicate: false);
 
+            if (record.Accepted)
+            {
+                _logger.LogInformation(
+                    "Match {MatchId}: seat {Seat} intent {IntentType} ({IntentId}) accepted. {State}",
+                    _matchId, seat, DescribeIntent(intent.Intent), intentId, DescribeTurnState());
+            }
+            else
+            {
+                _logger.LogWarning(
+                    "Match {MatchId}: seat {Seat} intent {IntentType} ({IntentId}) rejected {Code}: {Reason}. {State}",
+                    _matchId, seat, DescribeIntent(intent.Intent), intentId, record.Code, record.Reason,
+                    DescribeTurnState());
+            }
+
             if (!record.Accepted)
                 return;
 
@@ -462,6 +488,10 @@ public sealed class MatchGrain : IMatchGrain
         IntentRejectCode code,
         string reason)
     {
+        _logger.LogWarning(
+            "Match {MatchId}: seat {Seat} intent {IntentId} rejected before execution {Code}: {Reason}. {State}",
+            _matchId, seat, intentId, code, reason, DescribeTurnState());
+
         _intents[intentId] = new IntentRecord(false, code, reason, _engine.Events.Count);
 
         await PersistIntentAsync(new PersistedIntent(
@@ -510,6 +540,15 @@ public sealed class MatchGrain : IMatchGrain
         var from = Math.Max(1, fromSeq);
         var events = EventProjection.ProjectRange(_engine.Events, seat, from);
 
+        _logger.LogInformation(
+            "Match {MatchId}: events {FromSeq}..{ToSeq} to seat {Seat}: [{EventTypes}]. {State}",
+            _matchId,
+            from,
+            to,
+            seat,
+            string.Join(", ", events.Select(e => e.GetType().Name)),
+            DescribeTurnState());
+
         _seats[seat].SentSeq = to;
 
         await SendToSeatAsync(seat, new ServerEvents
@@ -524,6 +563,22 @@ public sealed class MatchGrain : IMatchGrain
     {
         var to = _engine.Events.Count;
         var view = MatchProjection.ForViewer(_engine, seat, _matchId, to, BuildClock(now));
+        var legalRides = string.Join(
+            ", ",
+            view.LegalIntents.OfType<RideIntent>().Select(i => i.PrintingId));
+
+        _logger.LogInformation(
+            "Match {MatchId}: snapshot to seat {Seat} at seq {Seq}, you={You}, active={Active}, turn={Turn}, phase={Phase}, legal={LegalCount}, rides=[{Rides}]. {State}",
+            _matchId,
+            seat,
+            to,
+            view.You,
+            view.ActivePlayer,
+            view.TurnNumber,
+            view.Phase,
+            view.LegalIntents.Count,
+            legalRides,
+            DescribeTurnState());
 
         _seats[seat].SentSeq = to;
 
@@ -780,6 +835,52 @@ public sealed class MatchGrain : IMatchGrain
         }
     }
 
+    private static string DescribeIntent(IntentPayload? intent) =>
+        intent is RideIntent ride
+            ? $"Ride({ride.PrintingId})"
+            : intent?.GetType().Name ?? "null";
+
+    /// <summary>
+    /// Diagnostic snapshot for ride issues: active player, phase, vanguard grade,
+    /// hand grades and cards that should be offered for a ride.
+    /// </summary>
+    private string DescribeTurnState()
+    {
+        var state = _engine.State;
+        var active = state.ActivePlayer;
+        var player = state.Players[active];
+        var rideGrade = _engine.VanguardGrade(active);
+
+        var vanguard = player.Vanguard is null
+            ? "none"
+            : $"{player.Vanguard.PrintingId}(g{rideGrade})";
+
+        var hand = string.Join(
+            ", ",
+            player.Hand.Select(card =>
+            {
+                var grade = state.Catalog.CardOf(card.PrintingId).Grade;
+                return $"{card.PrintingId}(g{grade})";
+            }));
+
+        var rideReady = state.Phase == Phase.Ride
+            ? string.Join(
+                ", ",
+                player.Hand
+                    .Where(card =>
+                    {
+                        var grade = state.Catalog.CardOf(card.PrintingId).Grade;
+                        return grade == rideGrade || grade == rideGrade + 1;
+                    })
+                    .Select(card => card.PrintingId)
+                    .Distinct())
+            : string.Empty;
+
+        return $"active={active} turn={state.TurnNumber} phase={state.Phase} " +
+               $"step={state.Step} vanguard={vanguard} hand=[{hand}] " +
+               $"rideReady=[{rideReady}]";
+    }
+
     private void RefreshSummary()
     {
         _summary = new MatchSummary(