chore(mcp): add @rlwj-lab/opsxdb-mcp npm launcher package

Node wrapper that spawns the Go opsxdb-mcp binary (OPSXDB_MCP_BIN / PATH).
Ready for npm publish --access public (requires 2FA OTP).

packages/opsxdb-mcp/bin/cli.js

@@ -0,0 +1,39 @@
+#!/usr/bin/env node
+'use strict';
+
+const { spawn } = require('child_process');
+const {
+  resolveBinary,
+  missingBinaryMessage,
+} = require('../dist/resolve-binary.js');
+
+const bin = resolveBinary();
+if (!bin) {
+  process.stderr.write(missingBinaryMessage());
+  process.exit(1);
+}
+
+const child = spawn(bin, process.argv.slice(2), {
+  stdio: 'inherit',
+  env: process.env,
+  windowsHide: true,
+});
+
+child.on('error', (err) => {
+  process.stderr.write(
+    `opsxdb-mcp: failed to start "${bin}": ${err.message}\n`
+  );
+  process.exit(1);
+});
+
+child.on('exit', (code, signal) => {
+  if (signal) {
+    try {
+      process.kill(process.pid, signal);
+    } catch {
+      process.exit(1);
+    }
+    return;
+  }
+  process.exit(code == null ? 1 : code);
+});