update CI workflow and enforce LF line endings

- Updated supported OS matrix in CI to include macOS and Windows.
- Bumped actions versions (checkout and setup-go) in CI.
- Updated GolangCI-Lint action to v9 and set version explicitly.
- Added `.gitattributes` to enforce LF line endings.
- Adjusted Go version in `go.mod` and CI matrix.

Author: stackus

.gitattributes

@@ -0,0 +1 @@
+*.go text eol=lf

.github/workflows/ci.yml

@@ -11,27 +11,30 @@ jobs:
   golangci:
     strategy:
       matrix:
-        go-version: [ 1.24.x ]
-        os: [ ubuntu-latest ]
+        go: [ stable ]
+        os: [ ubuntu-latest, macos-latest, windows-latest ]
     name: lint
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v6
+      - uses: actions/setup-go@v6
+        with:
+          go-version: ${{ matrix.go }}
       - name: golangci-lint
-        uses: golangci/golangci-lint-action@v3
+        uses: golangci/golangci-lint-action@v9
+        with:
+          version: v2.13
 
   test:
     strategy:
       matrix:
-        go-version: [ 1.24.x ]
+        go-version: [ 1.26.x ]
         os: [ ubuntu-latest, macos-latest, windows-latest ]
     runs-on: ${{ matrix.os }}
     steps:
-      - name: Install Go
-        uses: actions/setup-go@v3
+      - uses: actions/checkout@v6
+      - uses: actions/setup-go@v6
         with:
-          go-version: ${{ matrix.go-version }}
-      - name: Checkout code
-        uses: actions/checkout@v3
+          go-version: ${{ matrix.go }}
       - name: Test
         run: go test ./...

go.mod

@@ -1,6 +1,6 @@
 module github.com/stackus/errors
 
-go 1.26.8
+go 1.26.0
 
 require (
 	github.com/stretchr/testify v1.12.1