docs: add status badges to README

Add npm version, release, CI, codecov, and license badges in the same
style as the gittype README. Brand colors (#1e3a8a / #0f172a) from the
logo are applied to the npm and release badges.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: unhappychoice

README.md

@@ -2,6 +2,14 @@
   <img src="docs/images/logo.svg" alt="mdts" width="400">
 </h1>
 
+<p align="center">
+  <a href="https://www.npmjs.com/package/mdts"><img src="https://img.shields.io/npm/v/mdts.svg?style=flat-square&color=1e3a8a" alt="npm"></a>
+  <a href="https://github.com/unhappychoice/mdts/releases"><img src="https://img.shields.io/github/v/release/unhappychoice/mdts?style=flat-square&color=0f172a&label=release" alt="release"></a>
+  <a href="https://github.com/unhappychoice/mdts/actions/workflows/test.yml"><img src="https://img.shields.io/github/actions/workflow/status/unhappychoice/mdts/test.yml?branch=main&style=flat-square&label=CI" alt="CI"></a>
+  <a href="https://codecov.io/gh/unhappychoice/mdts"><img src="https://img.shields.io/codecov/c/github/unhappychoice/mdts?style=flat-square" alt="codecov"></a>
+  <a href="https://github.com/unhappychoice/mdts/blob/main/LICENSE.md"><img src="https://img.shields.io/npm/l/mdts.svg?style=flat-square" alt="license"></a>
+</p>
+
 <p align="center">
   (<strong>M</strong>)ark(<strong>d</strong>)own (<strong>T</strong>)ree (<strong>S</strong>)erver
   <br>