fix(infra): remove duplicate run key

Why:
- GitHub Actions rejected the workflow due to duplicate run
- restore valid main check job syntax

Impact:
- workflow YAML validates for main checks
- Tests: not run (workflow change)

Author: icepuma

.github/workflows/ci.yml

@@ -210,7 +210,6 @@ jobs:
         if: runner.os == 'Windows'
         shell: pwsh
         run: just check
-        run: just check
 
   build:
     name: Build - ${{ matrix.platform.os-name }}