ci: bump actions/checkout from 4 to 7

Bumps [actions/checkout](https://github.com/actions/checkout) from 4 to 7.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](https://github.com/actions/checkout/compare/v4...v7)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/ci.yml

@@ -157,7 +157,7 @@ jobs:
     runs-on: windows-latest
     timeout-minutes: 45
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - uses: actions/setup-python@v7
         with:
           python-version: ${{ env.PY_VERSION }}

.github/workflows/docs.yml

@@ -34,7 +34,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 15
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - name: Setup Node.js
         uses: actions/setup-node@v7

.github/workflows/opencode-plugin.yml

@@ -33,7 +33,7 @@ jobs:
       run:
         working-directory: plugins/opencode
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - uses: actions/setup-node@v7
         with:
           node-version: "20"

.github/workflows/tools-hash-refresh.yml

@@ -21,7 +21,7 @@ jobs:
   verify-pins:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
       - uses: actions/setup-python@v7
         with:
           python-version: "3.12"