Feat: Add Hugging Face Space as Client-Side Backend Integration

Issue Description:

Implement support for using a Hugging Face Space as an alternative backend for the client application. This allows the frontend to directly communicate with a deployed Hugging Face Space API for inference, transcription, summarization, or other AI tasks without depending solely on the existing local/server backend.

Objectives:

• Add configuration to connect frontend with Hugging Face Space endpoint.
• Support switching between current backend and Hugging Face Space backend.
• Handle API requests/responses from Hugging Face Space.
• Add environment variable for Space URL.
• Ensure proper loading, error, and timeout handling.
• Maintain existing functionality with current backend.

Scope:

• Update API service layer.
• Add backend selector/config option in frontend settings.
• Normalize response formats if Hugging Face Space output differs.
• Add fallback handling when Space is unavailable.
• Test end-to-end frontend integration.

Acceptance Criteria:

• Frontend can successfully call Hugging Face Space API.
• User can choose backend source.
• Errors are displayed gracefully.
• Existing backend flow remains unaffected.
• Deployment config supports environment-based endpoint changes.