Initial commit: Nexus Mission Control Platform

- ASP.NET Core 10 Backend (JWT Auth, Agent config API)
- Vue 3 Frontend (Dashboard, Team, Agents, Config Editor)
- PostgreSQL Database
- Docker Compose setup
- Mission Control Dashboard redesign

backend/Contracts/Responses.cs

@@ -0,0 +1,50 @@
+using Nexus.Api.Domain;
+
+namespace Nexus.Api.Contracts;
+
+public sealed record AgentListResponse(
+    string Id,
+    string Name,
+    string Role,
+    string Model,
+    string Status,
+    DateTimeOffset? LastSeen,
+    string? Workspace,
+    string? Description
+);
+
+public sealed record AgentDetailResponse(
+    string Id,
+    string Name,
+    string Role,
+    string Model,
+    string Status,
+    DateTimeOffset? LastSeen,
+    string? Workspace,
+    string? AgentDir,
+    string? Description,
+    IReadOnlyList<string>? SubAgents,
+    string? IdentityName
+);
+
+public sealed record AgentCommandRequest(string Message);
+
+public sealed record AgentCommandResponse(
+    string Runtime,
+    string AgentId,
+    string ConversationId,
+    string Content
+);
+
+public sealed record ProjectHealth(
+    int Online,
+    int Offline,
+    int Degraded,
+    int Unknown
+);
+
+public sealed record IncidentInfo(
+    Guid? TaskId,
+    string? Title,
+    DateTimeOffset? Since
+);