Remove LRE/LRO characters from results and error messages

[rudyhuyn]

Fixes #504

Calculation results, Memory items, History items and error messages should be displayed LtoR whatever the current culture.

To this end, the current version of the code relies on ViewModels to format the string and add special characters (0x202a, 0x202c or 0x202d) to force Xaml to display the text left-to-right.

This implementation isn't ideal and case many issues with the clipboard when users try to copy-paste the result of a calculation.

This PR will move the management of the direction of the text-flow from the data (strings in view-models) to the UI renderer using the XAML property FlowDirection.

Now that the strings are exempt of special characters, copy-paste will work correctly, whatever the application destination.

Description of the changes:

• remove all special characters to force a flow direction from all strings in view-models.
• force controls displaying these strings to render the data left-to-right

Example of the UI when we only remove the special characters

After we force Xaml to render controls left-to-right

How changes were validated:

• tested in English, arabian and hebrew.

[rudyhuyn]

🧹 cleaning