Add update Osdag feature

[Zehen-249]

Description

This PR introduces a new asynchronous update mechanism for Osdag. The system uses QProcess and a non-modal progress dialog to ensure a smooth user experience without freezing the UI.

Key Features Added

Asynchronous Updates:

• Uses QProcess instead of blocking subprocess.run, ensuring the main UI remains responsive.

Non-blocking Progress Dialog:

• The update dialog is non-modal, allowing users to continue using the application while the update runs.

Cross-Platform Conda/Pixi Support:

• Detects the correct paths for conda or pixi executables dynamically for Windows, Linux, and macOS.

Confirmation Before Update:

• Prompts the user before starting the update process.

Implementation Details

Refactored Update class in update_version_check module:

• Fetches the latest version from the Osdag downloads page.
• Compares it with the current version.
• Runs update commands (conda or pixi) asynchronously using QProcess.

Added output_signal and finished_signal for updating the GUI in real-time.

Created a progress dialog (QDialog) with:

• Status label
• Live log view (conda prompt output)

Integrated update flow with Check for Update menu option in osadgMainPage module

How to Test

• Go to Help → Check for Update in the Osdag application.
• Change __version___ variable to lower value in ._version module for testing, this ensure update available pop-up.
• If an update is available → A confirmation dialog appears.
• On confirmation, the update process starts in a non-blocking progress dialog.
• During update UI remains responsive.
• Real-time logs in the dialog.
• On completion → A message box indicates success or failure.