chore: introduce markdown lint (#137)

* add markdown lint configs

* add markdownlint in dev deps

* add linting script

Author: sghng

.markdownlint-cli2.yaml

@@ -0,0 +1 @@
+gitignore: true

.markdownlint.yaml

@@ -0,0 +1,7 @@
+line-length:
+  code_blocks: false # caught by prettier
+  tables: false
+no-duplicate-heading:
+  siblings_only: true
+no-inline-html: false
+first-line-h1: false # could be in front matter

package.json

@@ -1,13 +1,16 @@
 {
   "name": "sustechapplication",
   "scripts": {
+    "lint": "markdownlint-cli2 \"**.md\"",
+    "lint:fix": "bun run lint -- --fix",
     "serve": "docsify serve docs",
     "sort": "bunx sort-package-json"
   },
   "dependencies": {
     "docsify-cli": "^4.4.4"
   },
   "devDependencies": {
+    "markdownlint-cli2": "^0.17.2",
     "prettier": "^3.5.2"
   }
 }