Add GitHub Actions workflows

Author: c032

.github/workflows/check.yml

@@ -0,0 +1,26 @@
+name: "check"
+
+on:
+  workflow_call:
+  workflow_dispatch:
+
+jobs:
+  vet:
+    runs-on: "ubuntu-latest"
+    steps:
+      - name: "Checkout"
+        uses: "actions/checkout@v4"
+
+      - name: "`go vet`"
+        run: |
+          go vet ./...
+
+  test:
+    runs-on: "ubuntu-latest"
+    steps:
+      - name: "Checkout"
+        uses: "actions/checkout@v4"
+
+      - name: "Run tests."
+        run: |
+          go test -v ./...

.github/workflows/push.yml

@@ -0,0 +1,11 @@
+name: "push"
+
+on:
+  workflow_dispatch:
+  push:
+    branches:
+      - "master"
+
+jobs:
+  check:
+    uses: "./.github/workflows/check.yml"