feat: complete backend celery upload task and frontend integration

[ziyaudheenms]

Description

Implemented a background asynchronous processing architecture for venue media uploads using Celery and Redis. This setup shifts heavy asset processing out of the main FastAPI request cycle to optimize API response times.

Phase Category

• Phase 1: MVP Submission (Base Foundation)
• Phase 2/3: Feature Implementation or Modularization
• Phase 4: Scalability Optimization
• General (Documentation, Bugfix, Chore, etc.)

Tech Stack (For Phase 1 MVP Submissions)

• Frontend: Next.js, React, TypeScript, Redux Toolkit
• Backend: FastAPI (Python), Celery, Redis (Upstash)
• Database: PostgreSQL (SQLAlchemy)

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature / Module (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

Checklist:

• I have read the Contribution Guidelines.
• My code follows the community spirit and standards of the WeCode community.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• My changes generate no new warnings or errors.

AI Disclosure

• I did NOT use AI tools to generate this code.
• I used AI tools (e.g., Copilot, ChatGPT, Claude) to help write this code, and I have fully reviewed, tested, and understand the output.

Screenshots / Screen Recording (if applicable)