Display url when issue page can't be opened in browser

[florianraith]

Description

When executing artisan make:filament-issue without xdg-open or similar tools installed, there is no way to retrieve the generated URL. Instead, you receive an output like xdg-open: not found, which is not helpful. This issue can occur, for example, when developing in a Docker container where xdg-open is not installed (e.g. with sail).

This PR implements a simple error message when something goes wrong and additionally displays the generated link, allowing users to manually copy and paste the link into their browsers.

Visual changes

Before:

After:

Functional changes

• Code style has been fixed by running the composer cs command.
• Changes have been tested to not break existing functionality.
• Documentation is up-to-date.