Feature/bulk add download sources

[ADEMOLA200]

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Description

Adds bulk add functionality for download sources. Users can now paste multiple URLs (one per line) instead of adding them one by one.

Changes

• Add toggle between single and bulk add modes in download source modal

• Implement bulk add backend function to process multiple URLs

• Add textarea UI for bulk URL input (one URL per line)

• Add validation for multiple URLs

• Display success/failed counts and error messages

• Auto-close modal if all URLs added successfully

• Add translations for bulk add feature

Here is a video showing the changes:

https://github.com/user-attachments/assets/d57c122c-988f-469e-a630-ef6c28f7fccf

[sonarqubecloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud