fix: replace add-sidebar-content

[treckstar]

The add-sidebar-content command has been
replaced with add-menu-content in v6.

WHY

BEFORE - What was wrong? What was happening before this PR?

When installing FileManager with composer, the backpack:add-sidebar-content command causes an error to occur. This command has been replaced with backpack:add-menu-content in v6.
Error Link

AFTER - What is happening after this PR?

The command runs backpack:add-menu-content which functions as expected.

HOW

How did you achieve that, in technical terms?

Replaced the two commands in the file src/Console/Commands/Install.php

Is it a breaking change or non-breaking change?

Breaking

How can we test the before & after?

Create a new version of Laravel 10

laravel new test-backpack6-filemanager
cd test-backpack6-filemanager

Then follow the Installation instructions.

From your command line, require the package (this will also require barryvdh/laravel-elfinder):

composer require backpack/filemanager

Then run the install process:

php artisan backpack:filemanager:install

[pxpm]

Thank you for the bug report, and specially for the PR @treckstar 🙏

Wanna take this to the end until merging ? I can help you or I can take it from here if you don't have time/desire to finish it.

We have now menu components to use in the sidebar, so instead of returning the <li> ... we return a backpack component with the menu item: <x-backpack::menu-item title="Link title" icon="la la-toolbox" :link="backpack_url('some_url')" />.

Each theme will then display the menu item accordingly to their settings.

Let me know if you want to do the change or I should pick it from here.

Cheers

[treckstar]

Sure no problem, I made a quick update. Feel free to take over if needed. Backpack has been really great so far. 👍🏼

[pxpm]

Thanks again @treckstar 🙏