No trailing spaces when drawing on canvas

[EpicDima]

In AnsiLevel.NONE mode, trailing spaces will be added if they have a style (which of course will not be visible in this mode). This can be fixed, but:

1. It is convenient for some tests, where you need to clearly see that spaces are added to the right (for this you can simply specify any background for a Composable element). This is easier than including ANSI commands in the output, as there is a lot of excess, which is almost always unnecessary for a simple test.

2. It seems that AnsiLevel.NONE is not common, while limiting the possible functionality of a Mosaic-based application, therefore, in my opinion, there is nothing wrong with trailing spaces in such cases.

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• [x] CHANGELOG.md's "Unreleased" section has been updated, if applicable.