OPC # 0006: OPC Git Trunk-Based management

Co-authored-by: Copilot <copilot@github.com>

ControlPlane.Api/Endpoints/ImageBuildEndpoints.cs

@@ -2,6 +2,7 @@ using System.Diagnostics;
 using System.Text.Json;
 using System.Text.RegularExpressions;
 using ControlPlane.Api.Services;
+using ControlPlane.Core.Services;
 
 namespace ControlPlane.Api.Endpoints;
 
@@ -14,6 +15,7 @@ public static class ImageBuildEndpoints
         var group = app.MapGroup("/api/image").WithTags("Image");
 
         group.MapGet("/status",  GetStatus);
+        group.MapGet("/history", GetHistory);
         group.MapPost("/build",  TriggerBuild);
 
         // Post-provisioning verification helpers
@@ -28,6 +30,26 @@ public static class ImageBuildEndpoints
     private static async Task<IResult> GetStatus(ImageBuildService svc) =>
         Results.Ok(await svc.GetStatusAsync());
 
+    /// <summary>Returns recent DockerImage build records for the sparkline chart.</summary>
+    private static async Task<IResult> GetHistory(BuildHistoryService history, int limit = 30)
+    {
+        var all = await history.GetBuildsAsync();
+        var records = all
+            .Where(b => b.Kind == ControlPlane.Core.Models.BuildKind.DockerImage)
+            .Take(Math.Clamp(limit, 1, 100))
+            .Select(b => new
+            {
+                b.Id,
+                b.Status,
+                b.StartedAt,
+                b.DurationMs,
+                b.CommitSha,
+                b.ImageDigest,
+            })
+            .ToList();
+        return Results.Ok(records);
+    }
+
     /// <summary>
     /// Triggers a docker build and streams the output line-by-line as SSE.
     /// The build context is the repo root, which must be configured via