chore: add gitpod config file (halo-dev/console#410)

Signed-off-by: Ryan Wang <i@ryanc.cc>

.gitpod.yml

@@ -0,0 +1,14 @@
+ports:
+  - port: 8080
+    onOpen: open-browser
+
+tasks:
+  - init: npm install -g pnpm && pnpm install
+    command: pnpm serve
+
+vscode:
+  extensions:
+    - dbaeumer.vscode-eslint
+    - editorconfig.editorconfig
+    - esbenp.prettier-vscode
+    - johnsoncodehk.volar

README.md

@@ -11,6 +11,7 @@
 <a href="https://github.com/halo-dev/halo-admin/blob/master/LICENSE"><img alt="GitHub" src="https://img.shields.io/github/license/halo-dev/halo-admin?style=flat-square"></a>
 <a href="https://github.com/halo-dev/halo-admin/commits"><img alt="GitHub last commit" src="https://img.shields.io/github/last-commit/halo-dev/halo-admin.svg?style=flat-square"></a>
 <a href="https://github.com/halo-dev/halo-admin/actions"><img alt="GitHub Workflow Status" src="https://img.shields.io/github/workflow/status/halo-dev/halo-admin/Halo%20Admin%20CI?style=flat-square"/></a>
+<a href="https://gitpod.io/#https://github.com/halo-dev/halo-admin"><img alt="Gitpod ready-to-code" src="https://img.shields.io/badge/Gitpod-ready--to--code-blue?logo=gitpod&style=flat-square"/></a>
 </p>
 
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