ci, build: modernize toolchain — goreleaser, golangci-lint v2, Makefile-only tooling

.claude/.gitignore

@@ -0,0 +1,2 @@
+*
+!.gitignore

.github/workflows/main.yml

@@ -1,4 +1,4 @@
-name: Main
+name: main
 
 on:
   push:
@@ -8,69 +8,105 @@ on:
     branches:
       - '*'
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: ${{ github.ref != 'refs/heads/main' }}
+
 jobs:
+  test:
+    name: test
+    runs-on: ubuntu-22.04
+    timeout-minutes: 10
+    steps:
+      - uses: actions/checkout@v6
+
+      - uses: actions/setup-go@v6
+        with:
+          go-version-file: "go.mod"
+
+      - name: test
+        run: go test -v ./cmd/... ./src/...
+
+  integration:
+    name: integration
+    runs-on: ubuntu-22.04
+    timeout-minutes: 10
+    steps:
+      - uses: actions/checkout@v6
+
+      - uses: actions/setup-go@v6
+        with:
+          go-version-file: "go.mod"
+
+      - name: test-integration
+        run: go test -v -tags devel ./src/cmd/...
+
+  lint:
+    name: lint
+    runs-on: ubuntu-22.04
+    timeout-minutes: 10
+    steps:
+      - uses: actions/checkout@v6
+
+      - uses: actions/setup-go@v6
+        with:
+          go-version-file: "go.mod"
+
+      - uses: golangci/golangci-lint-action@v9
+        with:
+          version: v2.12.0
+          args: --verbose ./cmd/... ./src/...
+
   build:
-    name: build && tests for ${{ matrix.name }}
+    name: build ${{ matrix.name }}
     runs-on: ubuntu-22.04
+    timeout-minutes: 10
     env:
       CGO_ENABLED: '0'
     strategy:
+      fail-fast: false
       matrix:
         include:
           - name: linux amd64
             env:
               GOOS: linux
               GOARCH: amd64
-            runTests: true
-            deb_arch: amd64
-
           - name: linux 386
             env:
               GOOS: linux
               GOARCH: 386
-            runTests: false
-            deb_arch: i386
-
           - name: darwin amd64
             env:
               GOOS: darwin
               GOARCH: amd64
-            runTests: true
-
           - name: darwin arm64
             env:
               GOOS: darwin
               GOARCH: arm64
-            runTests: false
-
           - name: windows amd64
             env:
               GOOS: windows
               GOARCH: amd64
-            runTests: true
 
     steps:
-      - name: check out code into the Go module directory
-        uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
-      - name: set up Go 1.x
-        uses: actions/setup-go@v5
+      - uses: actions/setup-go@v6
         with:
           go-version-file: "go.mod"
-        id: go
-
-      - name: get dependencies
-        run: |
-          export GOPATH=$HOME/go
-          ./tools/install.sh
 
       - name: build
         env: ${{ matrix.env }}
         run: go build -v ./cmd/... ./src/...
 
-      - name: test
-        if: ${{ matrix.runTests }}
-        run: env ${{ matrix.osEnv }} go test -v ./cmd/... ./src/...
-
-      - name: lint
-        run: env ${{ matrix.osEnv }} gomodrun golangci-lint run  ./cmd/... ./src/... --verbose
+  goreleaser-check:
+    name: goreleaser check
+    runs-on: ubuntu-22.04
+    timeout-minutes: 5
+    steps:
+      - uses: actions/checkout@v6
+      - uses: goreleaser/goreleaser-action@v7
+        with:
+          distribution: goreleaser
+          version: v2.15.4
+          args: check