feat: add author name to skipped packages in Discord notifications

API Changes:
- Track author name along with package name and reason
- Extract author from pkg.author (string or object with name field)
- Default to "unknown" if author info not available

Workflow Changes:
- Display author in format: "package-name (by author) - reason"

Example Discord output:
📋 Skipped Packages
tpmjs-threejs-tool (by john-doe) - invalid tpmjs field
@scope/package-1 (by jane-smith) - missing tpmjs field

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

.github/workflows/sync-keyword.yml

@@ -59,7 +59,7 @@ jobs:
 
           # Store skipped packages for Discord
           if [ "$skipped" -gt 0 ]; then
-            skippedList=$(echo "$response" | jq -r '.data.skippedPackages[]? | "\(.name) - \(.reason)"' 2>/dev/null | paste -sd "\n" - || echo "")
+            skippedList=$(echo "$response" | jq -r '.data.skippedPackages[]? | "\(.name) (by \(.author)) - \(.reason)"' 2>/dev/null | paste -sd "\n" - || echo "")
             if [ -n "$skippedList" ]; then
               echo "$skippedList" > /tmp/skipped_packages.txt
             fi