ci: add least-privilege permissions to GitHub Actions workflows

Add explicit workflow-level permissions for CI, lint, Reviewdog, and release automation.

Allow Reviewdog to publish pull-request reviews.

Limit every other workflow to the scopes it uses.

Refs: APPSEC-164

Author: peter-matkovski

.github/workflows/ci.yaml

@@ -9,6 +9,9 @@ concurrency:
   group: ${{ github.workflow }}-${{ github.head_ref }}
   cancel-in-progress: true
 
+permissions:
+  contents: read
+
 jobs:
   test-build:
     name: 👷 Test & Build

.github/workflows/initiate_release.yml

@@ -7,6 +7,10 @@ on:
         description: "The new version number with 'v' prefix. Example: v1.40.1"
         required: true
 
+permissions:
+  contents: write
+  pull-requests: write
+
 jobs:
   init_release:
     name: 🚀 Create release PR

.github/workflows/lint.yaml

@@ -6,6 +6,9 @@ concurrency:
   group: ${{ github.workflow }}-${{ github.head_ref }}
   cancel-in-progress: true
 
+permissions:
+  contents: read
+
 jobs:
   lint:
     name: 👮 Lint

.github/workflows/reviewdog.yaml

@@ -6,6 +6,10 @@ concurrency:
   group: ${{ github.workflow }}-${{ github.head_ref }}
   cancel-in-progress: true
 
+permissions:
+  contents: read
+  pull-requests: write
+
 jobs:
   reviewdog:
     name: 🐶 Reviewdog