build(deps): bump actions/checkout from 4 to 6

Bumps [actions/checkout](https://github.com/actions/checkout) from 4 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v4...v6)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -14,7 +14,7 @@ jobs:
     name: ruff (lint + format)
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: actions/setup-python@v5
         with:
           python-version: "3.13"
@@ -65,7 +65,7 @@ jobs:
           - package: Animator3D
             python-version: "3.13"
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
@@ -93,7 +93,7 @@ jobs:
     runs-on: ubuntu-latest
     continue-on-error: true
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: dtolnay/rust-toolchain@stable
         with:
           components: clippy, rustfmt
@@ -111,7 +111,7 @@ jobs:
       run:
         working-directory: VibeGame
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: oven-sh/setup-bun@v2
         with:
           bun-version: "1.2.21"

.github/workflows/release.yml

@@ -21,7 +21,7 @@ jobs:
     name: Bump version
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: actions/setup-node@v4
         with:
           node-version: '20'
@@ -47,7 +47,7 @@ jobs:
       run:
         working-directory: VibeGame
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           ref: main
       - uses: actions/setup-node@v4