chore: simplify lint.yml - use centralized validation workflow

Author: CybotTM

.github/workflows/lint.yml

@@ -9,31 +9,6 @@ permissions:
   contents: read
 
 jobs:
-  markdown:
-    name: Markdown
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
-      - uses: DavidAnson/markdownlint-cli2-action@07035fd053f7be764496c0f8d8f9f41f98305101 # v22.0.0
-
-  yamllint:
-    name: YAML
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
-      - uses: ibiqlik/action-yamllint@2576378a8e339169678f9939646ee3ee325e845c # v3.1.1
-
-  shellcheck:
-    name: ShellCheck
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
-      - uses: ludeeus/action-shellcheck@00cae500b08a931fb5698e11e79bfbd38e612a38 # 2.0.0
-        with:
-          severity: error
-        env:
-          SHELLCHECK_OPTS: -x
-
   validate:
     name: Skill Validation
     uses: netresearch/skill-repo-skill/.github/workflows/validate.yml@main