feat: downgrade subscription when its expired

[lethanhdat762003]

What?

Why?

How?

Testing?

• Functional Testing
• Security
• Performance
• Error Handling
• Code Quality
• Documentation
• Database
• Deployment
• Final Review

Anything Else?

[gemini-code-assist]

Code Review

This pull request introduces device deactivation logic for downgraded organizations and integrates quota enforcement for bulk device creation. Feedback highlights a critical Django runtime error in the deactivation logic where .update() is called on a sliced queryset, along with a performance issue from using len() instead of .count(). Additionally, a potential quota leak was identified in the bulk creation endpoint because quota is reserved before validating the input data, which can result in unreleased quota for failed devices.

Important

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