Add harness app: agent orchestrator with cluster deployment

- Next.js app for orchestrating coding agent benchmarks (Claude Code, Codex, OpenCode)
- Dockerfile installs git, gh CLI, and agent CLIs for headless execution
- K8s deployment with workspace volume, sealed credentials for Claude + OpenCode
- Traefik IngressRoute at harness.coreworlds.io with internal-only middleware + TLS
- CI pipeline path filter for harness builds
- Fix OpenCode runtime flags (subcommand-based headless mode)

apps/harness/src/app/api/tasks/route.ts

@@ -0,0 +1,45 @@
+import { NextRequest, NextResponse } from "next/server";
+import { getAllTasks, createTask } from "@/lib/store";
+import { getAgentConfig } from "@/lib/agents";
+import { Task, TaskSpec } from "@/lib/types";
+
+export async function GET() {
+  return NextResponse.json(getAllTasks());
+}
+
+export async function POST(request: NextRequest) {
+  const spec: TaskSpec = await request.json();
+
+  if (!spec.slug || !spec.goal) {
+    return NextResponse.json({ error: "slug and goal are required" }, { status: 400 });
+  }
+
+  if (!spec.agentId) {
+    return NextResponse.json({ error: "agentId is required" }, { status: 400 });
+  }
+
+  const agentConfig = getAgentConfig(spec.agentId);
+  if (!agentConfig) {
+    return NextResponse.json(
+      { error: `Agent config not found: ${spec.agentId}` },
+      { status: 400 },
+    );
+  }
+
+  const task: Task = {
+    id: `task-${Date.now()}`,
+    slug: spec.slug,
+    goal: spec.goal,
+    project: spec.project || "—",
+    status: "pending",
+    iteration: 0,
+    maxIterations: spec.maxIterations || 6,
+    startedAt: null,
+    evals: {},
+    iterations: [],
+    spec,
+  };
+
+  const created = createTask(task);
+  return NextResponse.json(created, { status: 201 });
+}