feat: US-010 — Projects sidebar tree view and project detail routing

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/renderer/components/projects/ProjectDetail.tsx

@@ -0,0 +1,34 @@
+import { trpc } from '@/lib/trpc';
+
+type ProjectDetailProps = {
+  projectId: string;
+};
+
+export function ProjectDetail({ projectId }: ProjectDetailProps) {
+  const { data: project, isLoading } = trpc.projects.get.useQuery({ id: projectId });
+
+  if (isLoading) {
+    return (
+      <div className="flex items-center justify-center h-full text-sm text-muted-foreground">
+        Loading project...
+      </div>
+    );
+  }
+
+  if (!project) {
+    return (
+      <div className="flex items-center justify-center h-full text-sm text-muted-foreground">
+        Project not found
+      </div>
+    );
+  }
+
+  return (
+    <div className="p-6 max-w-4xl mx-auto">
+      <h1 className="text-2xl font-semibold text-foreground">{project.name}</h1>
+      <p className="text-sm text-muted-foreground mt-1">
+        Project detail view will be implemented in US-013.
+      </p>
+    </div>
+  );
+}