enhance stringToColor with a custom defined palette from DefaultStyles

[vishna]

Description

This change allows overriding and extending colors provided by stringToColor. You're now able to define custom colors in DefautStyles e.g.:

palette: {
  "primary": Colors.red,
  "secondary": Colors.blue
}

and later use it:

BackgroundAttribute("primary")

Why?

This is particularly useful if your app has multiple themes and some limited color set per each theme. Currently there is a big switch with hardcoded values in stringToColor which cannot be customized. This PR solves this problem without introducing any breaking changes.

Related Issues

There was no issue for this.

Type of Change

• ✨ New feature: Adds new functionality without breaking existing features.
• 🛠️ Bug fix: Resolves an issue without altering current behavior.
• 🧹 Code refactor: Code restructuring that does not affect behavior.
• ❌ Breaking change: Alters existing functionality and requires updates.
• 🧪 Tests: Adds new tests or modifies existing tests.
• 📝 Documentation: Updates or additions to documentation.
• 🗑️ Chore: Routine tasks, or maintenance.
• ✅ Build configuration change: Changes to build or deploy processes.

Suggestions

This switch could be a default palette https://github.com/singerdmx/flutter-quill/blob/master/lib/src/common/utils/color.dart#L4 🤔

[singerdmx]

@EchoEllet please have a look

[singerdmx]

[ +2 ms] Target dart2js failed: ProcessException: Process exited abnormally with exit code 1:
../../../../.pub-cache/hosted/pub.dev/image_cropper_platform_interface-5.0.0/lib/src/models/cropped_file/html.dart:32:38:
Error: The method 'UnmodifiableUint8ListView' isn't defined for the class 'CroppedFile'.
- 'CroppedFile' is from 'package:image_cropper_platform_interface/src/models/cropped_file/html.dart' ('../../../../.pub-cache/hosted/pub.dev/image_cropper_platform_interface-5.0.0/lib/src/models/cropped_file/html.dart').
return Future.value(UnmodifiableUint8ListView(_initBytes!));
^^^^^^^^^^^^^^^^^^^^^^^^^
Error: Compilation failed.

Not sure this error is related to your change.
@CatHood0 do you have a chance to have a look?

[CatHood0]

@CatHood0 do you have a chance to have a look?

I will. Does the failed build occur on any platform or is it only for a certain platform?

[CatHood0]

I think the version of the image_cropper could be the main problem (the last version of the package is 8.0.1):

flutter-quill/example/pubspec.yaml

Lines 37 to 38 in f93ce63

	# Plugins
	image_cropper: ^5.0.1

I will make a PR solving this soon

[CatHood0]

@singerdmx UnmodifiableUint8ListView is now deprecated since Dart 3.4 see this

[singerdmx]

Ah I see

[singerdmx]

I think the version of the image_cropper could be the main problem (the last version of the package is 8.0.1):

flutter-quill/example/pubspec.yaml

Lines 37 to 38 in f93ce63

	# Plugins
	image_cropper: ^5.0.1

I will make a PR solving this soon

@CatHood0 how did it go?

[singerdmx]

@vishna could you please rebase?

[vishna]

@singerdmx will do it now - I was off last week