Pasting image directly from clipboard

[Pratheek555]

Brief Title

Acceptance Criteria fulfillment

• [x] When the message input is focused and the user presses Ctrl + V, any image present in the clipboard is detected.
• [x] Normal text pasting behavior remains unchanged when the clipboard contains text only.
• [x] Non-image clipboard content (e.g., PDFs or unsupported files) does not trigger the image upload flow.

Fixes #1039

Video/Screenshots

https://github.com/user-attachments/assets/ee34ee08-b493-4d98-b189-f7615306faa8

PR Test Details

Note: The PR will be ready for live testing at https://rocketchat.github.io/EmbeddedChat/pulls/pr-<pr_number> after approval. Contributors are requested to replace <pr_number> with the actual PR number.