Add multi-language samples to AppHost page

src/frontend/src/components/SimpleAppHostCode.astro

@@ -4,15 +4,17 @@ import type { MarkerDefinition } from '@astrojs/starlight/expressive-code';
 
 export type MarkerValueType = MarkerDefinition | MarkerDefinition[] | undefined;
 export type CollapseValueType = string | string[] | undefined;
+export type LangType = 'csharp' | 'python' | 'nodejs' | 'go' | 'java';
 
 interface CodeProps {
+  lang?: LangType;
   mark?: MarkerValueType;
   collapse?: CollapseValueType;
 }
 
-const { mark, collapse } = Astro.props as CodeProps;
+const { lang = 'csharp', mark, collapse } = Astro.props as CodeProps;
 
-const cs = `
+const csharp = `
 var builder = DistributedApplication.CreateBuilder(args);
 
 // Add database resource
@@ -32,12 +34,110 @@ builder.AddViteApp("frontend", "../frontend")
 
 builder.Build().Run();
 `;
+
+const python = `
+var builder = DistributedApplication.CreateBuilder(args);
+
+// Add database resource
+var postgres = builder.AddPostgres("db")
+    .AddDatabase("appdata")
+    .WithDataVolume();
+
+// Add API service and reference the database
+var api = builder.AddUvicornApp("api", "../api", "main:app")
+    .WithUv()
+    .WithReference(postgres)
+    .WaitFor(postgres);
+
+// Add frontend service and reference the API
+builder.AddViteApp("frontend", "../frontend")
+    .WithHttpEndpoint(env: "PORT")
+    .WithReference(api);
+
+builder.Build().Run();
+`;
+
+const javascript = `
+var builder = DistributedApplication.CreateBuilder(args);
+
+// Add database resource
+var postgres = builder.AddPostgres("db")
+    .AddDatabase("appdata")
+    .WithDataVolume();
+
+// Add API service and reference the database
+var api = builder.AddNodeApp("api", "../api", "server.js")
+    .WithNpm()
+    .WithReference(postgres)
+    .WaitFor(postgres);
+
+// Add frontend service and reference the API
+builder.AddViteApp("frontend", "../frontend")
+    .WithHttpEndpoint(env: "PORT")
+    .WithReference(api);
+
+builder.Build().Run();
+`;
+
+const golang = `
+var builder = DistributedApplication.CreateBuilder(args);
+
+// Add database resource
+var postgres = builder.AddPostgres("db")
+    .AddDatabase("appdata")
+    .WithDataVolume();
+
+// Add API service and reference the database
+var api = builder.AddGolangApp("api", "../api")
+    .WithHttpEndpoint(env: "PORT")
+    .WithReference(postgres)
+    .WaitFor(postgres);
+
+// Add frontend service and reference the API
+builder.AddViteApp("frontend", "../frontend")
+    .WithHttpEndpoint(env: "PORT")
+    .WithReference(api);
+
+builder.Build().Run();
+`;
+
+const java = `
+var builder = DistributedApplication.CreateBuilder(args);
+
+// Add database resource
+var postgres = builder.AddPostgres("db")
+    .AddDatabase("appdata")
+    .WithDataVolume();
+
+// Add API service and reference the database
+var api = builder.AddSpringApp("api", "../api", "otel.jar")
+    .WithHttpEndpoint(port: 8080)
+    .WithReference(postgres)
+    .WaitFor(postgres);
+
+// Add frontend service and reference the API
+builder.AddViteApp("frontend", "../frontend")
+    .WithHttpEndpoint(env: "PORT")
+    .WithReference(api);
+
+builder.Build().Run();
+`;
+
+const codeMap: Record<LangType, string> = {
+  csharp,
+  python,
+  nodejs: javascript,
+  go: golang,
+  java,
+};
+
+const code = codeMap[lang];
 ---
 
 <Code
-  code={cs}
+  code={code}
   lang="cs"
-  title="C# — AppHost.cs"
+  title="AppHost.cs"
   mark={mark}
   collapse={collapse}
   collapseStyle={'collapsible-auto'}