docs: add mdlint and submission status

.github/workflows/markdownlint.yaml

@@ -0,0 +1,26 @@
+name: Markdown Lint
+
+on:
+  workflow_dispatch:
+  pull_request:
+    paths:
+      - 'docs/**'
+
+jobs:
+  markdownlint:
+    name: Markdown Lint
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+
+      - name: Use Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '18.x'
+
+      - name: Install markdownlint
+        run: npm install -g [email protected]
+
+      - name: Run markdownlint
+        run: markdownlint 'docs/**/*.{md,mdx}' --config .markdownlint.jsonc

docs/dev-guide/backend/Process-of-Submission-&-SelfTest.md

@@ -47,3 +47,22 @@ deactivate User
 Key: `submission:{userID}:{UUID}`
 
 Value: `{submission}`
+
+## Status
+
+SASTOJ 的评测状态有以下几种：
+
+|序号|含义|
+|---|---|
+|0|无效|
+|1|通过|
+|2|编译错误|
+|3|答案错误|
+|4|格式错误|
+|5|运行错误|
+|6|时间超限|
+|7|内存超限|
+|8|输出超限|
+|9|等待中|
+
+当评测中间件收到提交后，会将状态设置为 `9`，表示等待中。当评测完成后，会将状态设置为对应的状态。