fix: use tauri plugin opener to open url in tauri client

[weareoutman]

Description

Links are not working in latest cinny-desktop. This PR introduces tauri plugin opener to fix it.

Fixes cinnyapp/cinny-desktop#544 along with cinnyapp/cinny-desktop#559.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings

[weareoutman]

Find a solution without touching Cinny web codebase, see comments below cinnyapp/cinny-desktop#559 (comment).