feat(lint): add GitHub Actions workflow to lint all Markdown files

This workflow allows for manual triggering and checks all Markdown files
in the repository for linting issues, providing reports and suggested
fixes for any errors found.

.github/workflows/lint-all.yaml

@@ -0,0 +1,50 @@
+name: Lint All
+
+on:
+  workflow_dispatch:
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Install zhlint
+        run: yarn global add zhlint
+
+      - name: Lint all Markdown files
+        run: |
+          mkdir -p linted_output
+          file_list="linted_output/file_list.txt"
+          linted_failed_file=$(mktemp)
+          echo 0 > "$linted_failed_file"
+          find . -type f -name '*.md' | while read -r file; do
+            set +e
+            zhlint "$file"
+            if [ $? -ne 0 ]; then
+              echo 1 > "$linted_failed_file"
+              echo "$file" >> "$file_list"
+              output_file="linted_output/report_and_suggested_fixes/$file"
+              mkdir -p "$(dirname "$output_file")"
+              zhlint "$file" --output="$output_file" > "$output_file.log" 2>&1
+            fi
+            set -e
+          done
+          linted_failed=$(cat "$linted_failed_file")
+          rm "$linted_failed_file"
+          echo "linted_failed=$linted_failed" >> "$GITHUB_ENV"
+
+      - name: Upload linted Markdown
+        uses: actions/upload-artifact@v4
+        with:
+          name: linted-markdown
+          path: linted_output/
+
+      - name: Check lint errors
+        run: |
+          set -e
+          if [ "${{ env.linted_failed }}" -ne 0 ]; then
+            echo "Linting errors found. Please check the reports and suggested fixes in uploaded artifact."
+            exit 1
+          fi