feat(i18n): add french language

[theotime2005]

This pull request adds support for the French language to the application, including translations for the user interface and privilege escalation prompts. It introduces a new translation file for French, updates locale configurations, and provides a localized sudo prompt for macOS users.

Internationalization improvements:

• Added a complete French translation file fr.ts to the application, covering all major UI strings and messages.
• Updated the i18n initialization in i18n.ts to include French translations and added 'fr' to the list of supported locales. [1] [2]

Platform-specific localization:

• Added a French version of the macOS sudo prompt script sudo-askpass.osascript-fr.js, providing a localized privilege request dialog for French-speaking users.

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