fix(install): install runtime dependencies only (--omit=dev) (#203)

cli/install-runner.js

@@ -133,7 +133,11 @@ export function runNpmInstall(pluginRoot, { spawn = defaultSpawn, lockHandle } =
   console.error('Installing episodic-memory dependencies (first run only)...');
   console.error('This may take 30-60 seconds...');
 
-  const child = spawn(npmCommand, ['install', '--no-audit', '--no-fund'], {
+  // --omit=dev: the plugin runs prebuilt dist/, so dev tooling (tsx, esbuild,
+  // vitest, typescript) is never loaded at runtime. Skipping it makes this
+  // install smaller and faster, and drops native postinstall steps (esbuild's
+  // binary check) that can fail the whole install (#203).
+  const child = spawn(npmCommand, ['install', '--omit=dev', '--no-audit', '--no-fund'], {
     cwd: pluginRoot,
     stdio: ['ignore', 'pipe', 'pipe'],
     shell: isWindows, // On Windows, we need shell: true to find npm.cmd

test/mcp-install-runner.test.ts

@@ -119,6 +119,21 @@ describe('install-runner — runNpmInstall termination handling (#161)', () => {
     expect(process.listenerCount('exit')).toBe(beforeExit);
   });
 
+  it('installs runtime dependencies only (--omit=dev) (#203)', async () => {
+    const child = makeFakeChild();
+    const fakeSpawn = vi.fn((..._args: unknown[]) => child);
+    const install = runNpmInstall(root, { spawn: fakeSpawn });
+
+    const [command, args, options] = fakeSpawn.mock.calls[0] as [string, string[], { cwd: string }];
+    expect(command).toMatch(/^npm(\.cmd)?$/);
+    expect(args[0]).toBe('install');
+    expect(args).toContain('--omit=dev');
+    expect(options.cwd).toBe(root);
+
+    child.emit('exit', 0);
+    await install.promise;
+  });
+
   it('resolves and removes handlers when the child exits 0 normally (no termination)', async () => {
     const beforeSigterm = process.listenerCount('SIGTERM');