ci: integrate golangci-lint with CI and update project documentation

- Add a GitHub Actions workflow to run golangci-lint on pushes and pull requests to master
- Display golangci-lint status badge in the README

Signed-off-by: Bo-Yi Wu <[email protected]>

Author: appleboy

.github/workflows/golangci-lint.yml

@@ -0,0 +1,34 @@
+name: golangci-lint
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+  workflow_dispatch: # Allow manual trigger
+
+permissions:
+  contents: read
+  pull-requests: read # Required for pull request comments
+
+jobs:
+  golangci:
+    name: golangci-lint
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v6
+
+      - name: Set up Go
+        uses: actions/setup-go@v6
+        with:
+          go-version: "1.24"
+          cache: true
+
+      - name: Setup golangci-lint
+        uses: golangci/golangci-lint-action@v9
+        with:
+          version: v2.6
+          args: --verbose

README.md

@@ -1,6 +1,7 @@
 # Gin Examples
 
 [![Trivy Security Scan](https://github.com/gin-gonic/examples/actions/workflows/trivy-scan.yml/badge.svg)](https://github.com/gin-gonic/examples/actions/workflows/trivy-scan.yml)
+[![golangci-lint](https://github.com/gin-gonic/examples/actions/workflows/golangci-lint.yml/badge.svg)](https://github.com/gin-gonic/examples/actions/workflows/golangci-lint.yml)
 
 This repository contains a number of ready-to-run examples demonstrating various use cases of [Gin](https://github.com/gin-gonic/gin).