Add deployment status badges to environment nodes in topology graph

Each environment node now shows pill badges at the bottom:
- Deploying (blue, pulsing) — count of active deployments
- Pending (amber, pulsing) — count awaiting approval
- Failed (red) — count of failed deployments
- Total (muted) — historical deployment count
- Agent warning (!) — when no agent is assigned

Badges pulse with CSS animation (respects prefers-reduced-motion).
Native SVG <title> elements provide hover tooltips.
Backend enriches TopologyPositionedNode with deployment counts
from promotion path statuses and agent assignment data.
Also fixes duplicate environment IDs causing layout API 400 errors.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/Platform/StellaOps.Platform.WebService/Contracts/TopologyLayoutModels.cs

@@ -24,7 +24,12 @@ public sealed record TopologyPositionedNode(
     int TargetCount,
     string? CurrentReleaseId,
     bool IsFrozen,
-    int PromotionPathCount);
+    int PromotionPathCount,
+    int DeployingCount,
+    int PendingCount,
+    int FailedCount,
+    int TotalDeployments,
+    string? AgentStatus);
 
 public sealed record TopologyRoutedEdge(
     string Id,

src/Platform/StellaOps.Platform.WebService/Services/TopologyLayoutService.cs

@@ -12,7 +12,7 @@ public sealed class TopologyLayoutService
 {
     private const double RegionPadding = 30;
     private const double EnvironmentNodeWidth = 180;
-    private const double EnvironmentNodeHeight = 72;
+    private const double EnvironmentNodeHeight = 76;
 
     private readonly TopologyReadModelService readModel;
     private readonly IElkLayoutEngine elkLayout;
@@ -50,7 +50,10 @@ public sealed class TopologyLayoutService
             .ConfigureAwait(false);
 
         var regions = regionsTask.Result.Items;
-        var environments = environmentsTask.Result.Items;
+        var environments = environmentsTask.Result.Items
+            .GroupBy(e => e.EnvironmentId, StringComparer.OrdinalIgnoreCase)
+            .Select(g => g.First())
+            .ToList();
         var paths = pathsTask.Result.Items;
         var gates = gatesTask.Result.Items;
         var hosts = hostsTask.Result.Items;
@@ -92,8 +95,14 @@ public sealed class TopologyLayoutService
             });
         }
 
+        var seenEnvIds = new HashSet<string>(StringComparer.Ordinal);
         foreach (var env in environments)
         {
+            if (!seenEnvIds.Add($"env-{env.EnvironmentId}"))
+            {
+                continue;
+            }
+
             elkNodes.Add(new ElkNode
             {
                 Id = $"env-{env.EnvironmentId}",
@@ -188,7 +197,12 @@ public sealed class TopologyLayoutService
                     TargetCount: region?.TargetCount ?? 0,
                     CurrentReleaseId: null,
                     IsFrozen: false,
-                    PromotionPathCount: 0);
+                    PromotionPathCount: 0,
+                    DeployingCount: 0,
+                    PendingCount: 0,
+                    FailedCount: 0,
+                    TotalDeployments: 0,
+                    AgentStatus: null);
             }
             else
             {
@@ -197,6 +211,15 @@ public sealed class TopologyLayoutService
                     string.Equals(e.EnvironmentId, envId, StringComparison.OrdinalIgnoreCase));
                 var health = ResolveEnvironmentHealth(envId, targetsByEnv);
                 var latestRelease = ResolveLatestRelease(envId, targetsByEnv);
+                var envPaths = paths.Where(p =>
+                    string.Equals(p.TargetEnvironmentId, envId, StringComparison.OrdinalIgnoreCase)
+                    || string.Equals(p.SourceEnvironmentId, envId, StringComparison.OrdinalIgnoreCase)).ToList();
+                var deployingCount = envPaths.Count(p => p.Status is "running" or "deploying");
+                var pendingCount = envPaths.Count(p => p.Status is "pending" or "awaiting_approval" or "gates_running");
+                var failedCount = envPaths.Count(p => p.Status is "failed");
+                var totalDeployments = envPaths.Count;
+
+                var agentStatus = ResolveAgentStatus(envId, targetsByEnv);
 
                 return new TopologyPositionedNode(
                     Id: node.Id,
@@ -215,7 +238,12 @@ public sealed class TopologyLayoutService
                     TargetCount: env?.TargetCount ?? 0,
                     CurrentReleaseId: latestRelease,
                     IsFrozen: false,
-                    PromotionPathCount: env?.PromotionPathCount ?? 0);
+                    PromotionPathCount: env?.PromotionPathCount ?? 0,
+                    DeployingCount: deployingCount,
+                    PendingCount: pendingCount,
+                    FailedCount: failedCount,
+                    TotalDeployments: totalDeployments,
+                    AgentStatus: agentStatus);
             }
         }).ToList();
 
@@ -321,4 +349,27 @@ public sealed class TopologyLayoutService
             .Select(t => t.ReleaseId)
             .FirstOrDefault();
     }
+
+    private static string? ResolveAgentStatus(
+        string environmentId,
+        Dictionary<string, List<TopologyTargetProjection>> targetsByEnv)
+    {
+        if (!targetsByEnv.TryGetValue(environmentId, out var envTargets) || envTargets.Count == 0)
+        {
+            return null;
+        }
+
+        var agentIds = envTargets
+            .Where(t => !string.IsNullOrEmpty(t.AgentId))
+            .Select(t => t.AgentId)
+            .Distinct(StringComparer.OrdinalIgnoreCase)
+            .ToList();
+
+        if (agentIds.Count == 0)
+        {
+            return "no_agent";
+        }
+
+        return "active";
+    }
 }