Implement Drag & Drop Support for TEXT/CSV Files in DeckPicker

[SanjaySargam]

Purpose / Description

Implement Drag&Drop TEXT file in DeckPicker

Fixes

• Fixes [Feature Request] Implement Drag&Drop TEXT file in DeckPicker #17855

Approach

Modify the drag-and-drop handler to check for .txt and .csv files. If valid, call the onSelectedCsvForImport function to handle the import process.

How Has This Been Tested?

Physical Device ( Redmi Note 11 )

WhatsApp.Video.2025-01-25.at.1.46.32.AM.mp4

Checklist

Please, go through these checks before submitting the PR.

• You have a descriptive commit message with a short title (first line, max 50 chars).
• You have commented your code, particularly in hard-to-understand areas
• You have performed a self-review of your own code
• UI changes: include screenshots of all affected screens (in particular showing any new or changed strings)
• UI Changes: You have tested your change using the Google Accessibility Scanner

[david-allison]

Looks good, cheers!

Is this feasible to test, or could a @NeedsTest be added

[david-allison]

No need to re-request approval if only minor changes are made, still good to go :)

[SanjaySargam]

Unit tests deferred for a faster merge; will be added later.