feat: add Aspire dashboard OTEL workflow

Add OTLP export wiring for the sidecar and dev scripts to launch the standalone Aspire Dashboard during development.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

scripts/dev-with-otel.ts

@@ -0,0 +1,57 @@
+import { spawn } from 'node:child_process';
+import { dirname, resolve } from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+import {
+  createOpenTelemetryEnvironment,
+  startAspireDashboard,
+  stopAspireDashboard,
+} from './aspireDashboard';
+
+const scriptDirectory = dirname(fileURLToPath(import.meta.url));
+const repositoryRoot = resolve(scriptDirectory, '..');
+const signalExitCodes: Partial<Record<NodeJS.Signals, number>> = {
+  SIGINT: 130,
+  SIGTERM: 143,
+};
+
+const dashboard = await startAspireDashboard();
+
+console.log(`Aspire Dashboard: ${dashboard.dashboardUrl}`);
+console.log(`Aryx sidecar OTLP endpoint: ${dashboard.otlpGrpcEndpoint}`);
+
+const child = spawn(process.execPath, ['run', 'dev'], {
+  cwd: repositoryRoot,
+  env: createOpenTelemetryEnvironment(process.env, dashboard.otlpGrpcEndpoint),
+  stdio: 'inherit',
+  windowsHide: true,
+});
+
+for (const signal of ['SIGINT', 'SIGTERM'] as const) {
+  process.on(signal, () => {
+    if (child.exitCode === null && child.signalCode === null) {
+      child.kill(signal);
+    }
+  });
+}
+
+let exitResult: { code: number | null; signal: NodeJS.Signals | null };
+
+try {
+  exitResult = await new Promise((resolve, reject) => {
+    child.on('error', reject);
+    child.on('exit', (code, signal) => {
+      resolve({ code, signal });
+    });
+  });
+} finally {
+  if (dashboard.startedByScript) {
+    await stopAspireDashboard();
+  }
+}
+
+if (exitResult.signal) {
+  process.exitCode = signalExitCodes[exitResult.signal] ?? 1;
+} else {
+  process.exitCode = exitResult.code ?? 1;
+}