[BUG] Paste Header Input Returns 400 Error and Conflicts with EML Upload

[useru1k]

Description:

In the current implementation, there are two input methods available:

1. Upload .eml file
2. Paste header content

• The "Paste Header" option is not functioning correctly and returns a 400 error when submitting content.

Additionally, there is a conflict between the two input methods:

• When an .eml file is uploaded, any previously pasted header content should be cleared.
• When header content is pasted, any previously uploaded .eml file should be removed.
  Currently, this mutual exclusivity is not properly handled.

Expected Behavior:

• Pasted header content should be processed successfully without errors.
• Only one input method should be active at a time:
  • Uploading a file clears pasted content
  • Pasting content removes uploaded file