fix: use table output and GITHUB_ENV for registry list validation

Avoids jq dependency and wrapper stdout pollution. Captures table-format
output via GITHUB_ENV multiline syntax, then validates header and first
data row with regex (same pattern as the version check step).

https://claude.ai/code/session_01Y8NseCm28GqE8nQ1Yvg5aa

Author: claude

.github/workflows/setup-stackql-test.yml

@@ -29,18 +29,30 @@ jobs:
       with:
         use_wrapper: ${{matrix.use_wrapper}}
 
-    - name: Run Registry List and Validate
+    - name: Run Registry List
+      id: run-registry-list
       run: |
-        OUTPUT=$(stackql exec --output json "REGISTRY LIST")
-        echo "Registry list output:"
-        echo "$OUTPUT"
+        echo "registry_list_output<<EOF" >> $GITHUB_ENV
+        stackql exec "REGISTRY LIST" >> $GITHUB_ENV
+        echo "EOF" >> $GITHUB_ENV
 
-        # When the wrapper is active, @actions/exec also prints the command line before the
-        # output, and core.debug() appends ::debug:: annotations immediately after the JSON
-        # (on the same line, since the JSON has no trailing newline). Strip workflow commands
-        # and then keep only lines that look like JSON (starting with [ or {).
-        CLEAN_JSON=$(echo "$OUTPUT" | sed 's/::[a-z-]*::.*$//' | grep -E '^\s*[\[{]')
+    - name: Validate Registry List
+      run: |
+        echo "Registry list output:"
+        echo "${{ env.registry_list_output }}"
+
+        # Validate header row: expect | provider | and | version | columns
+        HEADER_REGEX='\|\s*provider\s*\|\s*version\s*\|'
+        if ! [[ "${{ env.registry_list_output }}" =~ $HEADER_REGEX ]]; then
+          echo "Registry list header does not match expected format"
+          exit 1
+        fi
+
+        # Validate at least one data row: | <name> | v<major>.<minor>.<patch> |
+        DATA_ROW_REGEX='\|\s*[a-z][a-z0-9_]*\s*\|\s*v[0-9]+\.[0-9]+\.[0-9]+\s*\|'
+        if ! [[ "${{ env.registry_list_output }}" =~ $DATA_ROW_REGEX ]]; then
+          echo "Registry list does not contain a valid data row"
+          exit 1
+        fi
 
-        # Validate JSON structure: array of objects each with provider and version keys
-        echo "$CLEAN_JSON" | jq -e 'type == "array" and (all(.[]; has("provider") and has("version")))' > /dev/null
         echo "Registry list validated successfully."