Production-ready improvements: security hardening, Redis sessions, retry logic, updated pricing

Changes:
- Removed hardcoded admin credentials (now requires env vars)
- Added Redis session storage with in-memory fallback
- Improved CORS configuration with warnings for development mode
- Added retry_with_backoff decorator for translation API calls
- Updated pricing: Starter=, Pro=, Business=
- Stripe price IDs now loaded from environment variables
- Added redis to requirements.txt
- Updated .env.example with all new configuration options
- Created COMPREHENSIVE_REVIEW_AND_PLAN.md with deployment roadmap
- Frontend: Updated pricing page, new UI components

sample_files/.~lock.complex_sample.docx#

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-,ramez,simorgh,30.11.2025 09:24,C:/Users/ramez/AppData/Local/onlyoffice;