ci: Use least privilege principle for permissions

Declares only the required permissions per workflow.

Author: matz3

.github/workflows/ci.yml

@@ -7,6 +7,9 @@ on:
     branches:
       - main
 
+# No permissions are required for this workflow
+permissions: {}
+
 jobs:
   test:
     name: General checks, tests and coverage reporting

.github/workflows/commitlint.yml

@@ -8,6 +8,10 @@ on:
     branches:
       - main
 
+permissions:
+  contents: read
+  pull-requests: read
+
 jobs:
   commitlint:
     runs-on: ubuntu-latest

.github/workflows/e2e.yml

@@ -9,6 +9,9 @@ on:
       - main
   workflow_dispatch:
 
+# No permissions are required for this workflow
+permissions: {}
+
 jobs:
   e2e:
     runs-on: ubuntu-24.04

.github/workflows/issues.yml

@@ -3,6 +3,10 @@ on:
   schedule:
     - cron: '00 20 * * *'
 
+permissions:
+  issues: write
+  pull-requests: write
+
 jobs:
   stale:
     name: Flag and close stale issues

.github/workflows/reuse-compliance.yml

@@ -8,6 +8,9 @@ on:
     branches:
       - main
 
+# No permissions are required for this workflow
+permissions: {}
+
 jobs:
   compliance-check:
     name: Compliance Check

.github/workflows/test.yml

@@ -8,6 +8,9 @@ on:
     branches:
       - main
 
+# No permissions are required for this workflow
+permissions: {}
+
 jobs:
   test:
     name: Unit and Integration