* Fixing LocalFileComparator output

* Fixing path separators for windows failures

* Windows path issues

* Testing

* ++

* ++

* Fixing base directory - windows

* Clean up

* Create 'center' template

* Implement DropdownButton.selectedItemBuilder

* Add constraints property, updated default constraints for ToggleButtons to 48x48

* Add kMinInteractiveDimension constant to ToggleButtons

On macOS and iOS, the build mode is converted to lowercase in the
Flutter-side script, allowing projects to pass configuration names
directly. This adds the same behavior to the tool_backend.dart script
currently used by Windows and Linux, so that Windows builds can do the
same (since the default configuration names used by VS, as in Xcode,
start with a capital letter).

Make FlutterPluginRegistrant a static framework so add-to-app can use plugins with static frameworks (#40401)

- Makes build_macos.dart handle the case where there is only one Xcode
  project in the macos/ directory, but it's not called Runner.xcodeproj
- Makes getInfo throw a tool exit when trying to get project info and it
  can't find a project, since that is a configuration error by the user
  rather than a tool bug.

This was part of a disused tool to explain what did and did not run after reload.

Fixes a crash introduced on #40011 due to an incorrect type in the vswhere search

Fixes #40238