V11: Using IFileProvider to access assets added from packages (#13141)

* Creating a FileProviderFactory for getting the package.manifest and grid.editors.config.js files through a file provider

* Collecting the package.manifest-s from different sources

* Searching different sources for grid.editors.config.js

* Using an IFileProvider to collect all tours

* Refactoring IconService.cs

* Typo

* Optimizations when looping through the file system

* Moving WebRootFileProviderFactory to Umbraco.Web.Common proj

* Removes double registering

* pluginLangFileSources includes the localPluginFileSources

* Comments

* Remove linq from foreach

* Change workflow for grid.editors.config.js so we check first physical file, then RCL, then Embedded

* Clean up

* Check if config dir exists

* Discover nested package.manifest files

* Fix IFileInfo.PhysicalPath check

* Revert 712810e1fd995720047832ee689f804185ea69d6 as that way files in content root are preferred over those in web root

* Adding comments

* Refactoring

* Remove PhysicalPath check

* Fix registration of WebRootFileProviderFactory

src/Umbraco.Core/IO/IGridEditorsConfigFileProviderFactory.cs

@@ -0,0 +1,10 @@
+using Microsoft.Extensions.FileProviders;
+
+namespace Umbraco.Cms.Core.IO;
+
+/// <summary>
+///     Factory for creating <see cref="IFileProvider" /> instances for providing the grid.editors.config.js file.
+/// </summary>
+public interface IGridEditorsConfigFileProviderFactory : IFileProviderFactory
+{
+}