[DevTask] Clean up temporary git download notification

[webfiltered]

Replace native dialog (added to notify users needing to install git) with proper frontend page and guidance.

Added in:
2e0ad3b

┆Issue is synchronized with this Notion page by Unito

[dosubot]

Hi, @webfiltered. I'm Dosu, and I'm helping the desktop team manage their backlog. I'm marking this issue as stale.

Issue Summary:

• Suggestion to replace native dialog for git installation with a user-friendly frontend page.
• Aimed at enhancing user experience.
• Initially introduced in a specific commit and tracked on a Notion page.
• No further comments or developments since the issue was raised.

Next Steps:

• Please confirm if this issue is still relevant to the latest version of the desktop repository by commenting here.
• If no updates are provided, the issue will be automatically closed in 7 days.

Thank you for your understanding and contribution!

[webfiltered]

Native dialog framework landing in frontend 1.27.

• Add desktop dialogs framework ComfyUI_frontend#5605