fix(cli): make clean source checkouts start reliably

scripts/rea.mjs

@@ -1,5 +1,9 @@
 #!/usr/bin/env node
 
+import { access } from "node:fs/promises";
+import { dirname, resolve } from "node:path";
+import { fileURLToPath } from "node:url";
+
 // Route production MCP before importing Incur. Incur owns registration helpers
 // such as `mcp add`, while only dist/main.js may serve the 78-tool stdio server.
 const args = process.argv.slice(2);
@@ -9,8 +13,17 @@ const { default: packageJson } = await import("../package.json", {
 process.env.REA_PACKAGE_VERSION = packageJson.version;
 const isMcpMode =
   args.length === 1 && (args[0] === "--mcp" || args[0] === "mcp");
+const packageRoot = resolve(dirname(fileURLToPath(import.meta.url)), "..");
+const runtimeFiles = isMcpMode
+  ? ["dist/main.js"]
+  : ["dist/cli.js", "dist/cliOutput.js"];
 
-if (isMcpMode) {
+if (!(await compiledRuntimeExists(runtimeFiles))) {
+  process.stderr.write(
+    `REA's compiled runtime is missing. Run \`npm ci\` in ${packageRoot} to install dependencies and build REA, then restart it. If this is an installed package, reinstall rea-agents.\n`,
+  );
+  process.exitCode = 1;
+} else if (isMcpMode) {
   const { runEntrypoint } = await import("../dist/main.js");
   await runEntrypoint();
 } else {
@@ -20,3 +33,24 @@ if (isMcpMode) {
     stdout: (output) => process.stdout.write(sanitizeCliOutput(output)),
   });
 }
+
+async function compiledRuntimeExists(paths) {
+  for (const path of paths) {
+    try {
+      await access(resolve(packageRoot, path));
+    } catch (cause) {
+      if (isMissing(cause)) return false;
+      throw cause;
+    }
+  }
+  return true;
+}
+
+function isMissing(cause) {
+  return (
+    typeof cause === "object" &&
+    cause !== null &&
+    "code" in cause &&
+    cause.code === "ENOENT"
+  );
+}