feat: consolidate env config and add deployment files

- Add debug_font_path, demo_docs_dir, e2e_api_base_url to config.py
- Fix hardcoded paths in pp_structure_debug.py, create_demo_images.py
- Fix hardcoded paths in test files
- Update .env.example with new configuration options
- Update .gitignore to exclude AI development files (.claude/, openspec/, AGENTS.md, CLAUDE.md)
- Add production startup script (start-prod.sh)
- Add README.md with project documentation
- Add 1panel Docker deployment files (docker-compose.yml, Dockerfiles, nginx.conf)

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/src/pages/TaskDetailPage.tsx

@@ -147,7 +147,7 @@ export default function TaskDetailPage() {
 
   // Construct PDF URL for preview - memoize to prevent unnecessary reloads
   // Must be called unconditionally before any early returns (React hooks rule)
-  const API_BASE_URL = import.meta.env.VITE_API_BASE_URL || 'http://localhost:8000'
+  const API_BASE_URL = (import.meta.env.VITE_API_BASE_URL || '').replace(/\/$/, '')
   const pdfUrl = useMemo(() => {
     return taskId ? `${API_BASE_URL}/api/v2/tasks/${taskId}/download/pdf` : ''
   }, [taskId, API_BASE_URL])