chore(deps): Bump actions/checkout from 4 to 6

.github/workflows/ci.yml

@@ -21,7 +21,7 @@ jobs:
       matrix:
         python: ["3.10", "3.11", "3.12", "3.13"]
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Install uv
         uses: astral-sh/setup-uv@v3
@@ -56,7 +56,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 5
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Install uv
         uses: astral-sh/setup-uv@v3
@@ -93,7 +93,7 @@ jobs:
       # fetch-depth: 0 so gitleaks scans every commit on the branch, not just
       # the tip — secrets that were briefly committed and then removed still
       # live in history and remain harvestable.
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0
 

.github/workflows/release.yml

@@ -16,7 +16,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 10
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Install uv
         uses: astral-sh/setup-uv@v3

.github/workflows/sync-upstream.yml

@@ -19,7 +19,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 15
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Install uv
         uses: astral-sh/setup-uv@v3