feat: only one CI job at a time per PR

This prevents the Gitea runner from getting clogged up with stale CI checks.

.gitea/workflows/ci.yml

@@ -1,5 +1,9 @@
 name: CI
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 on:
   push:
     branches: [main]
@@ -7,7 +11,6 @@ on:
 
 jobs:
   lint:
-    name: Golang Lint
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
@@ -16,15 +19,11 @@ jobs:
         with:
           go-version-file: go.mod
 
-      - name: Check go mod tidy
-        run: go mod tidy && git diff --exit-code go.mod go.sum
-
       - uses: golangci/golangci-lint-action@v7
         with:
           version: latest
 
   unit-test:
-    name: Unit Tests
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
@@ -37,7 +36,6 @@ jobs:
         run: go test ./... -cover -v
 
   fuzz-test:
-    name: Fuzz Tests
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
@@ -53,7 +51,6 @@ jobs:
           done
 
   mutation-test:
-    name: Mutation Tests
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4

go.sum

@@ -4,7 +4,6 @@ github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZb
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
 github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
-gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=