feat(notification): add support for Ntfy

[liheji]

feat(notification): add support for Ntfy

• Implement Ntfy external notifier in Go
• Add Ntfy configuration component in Vue
• Update language files with Ntfy translations- Register Ntfy notifier in the main application

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[Copilot]

Pull Request Overview

This PR adds support for Ntfy as an external notification service. The implementation includes a Go backend notifier that handles Ntfy API communication and a Vue frontend configuration component for user setup.

• Implement Ntfy external notifier with authentication support (Bearer token and Basic auth)
• Add Vue configuration component for Ntfy settings
• Update language files to include Ntfy translations

Reviewed Changes

Copilot reviewed 17 out of 17 changed files in this pull request and generated 5 comments.

File	Description
internal/notification/ntfy.go	Core Ntfy notifier implementation with HTTP client and message formatting
app/src/views/preference/components/ExternalNotify/ntfy.ts	Vue configuration component defining Ntfy settings form
app/src/views/preference/components/ExternalNotify/index.ts	Register Ntfy config in the notification system
app/src/language/*/app.po	Add "Ntfy" translation entries across all supported languages

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[0xJacky]

LGTM 🎉