[Feature Request]: Metadata structure of stream - add currency, decimal and grouping symbols

### What would you like to happen?

Among the data returned by **Metadata structure of stream**, the symbols for currency, decimal point and thousand grouping may be added.

Those can be useful for Metadata Injection in certain components, to allow e.g. numbers formatted in non-Java standard to be parsed correctly.

_(The format mask had already been added in #3120, but it's not enough to do so)_

### Issue Priority

Priority: 3

### Issue Component

Component: Transforms, Component: Hop Gui

Start by locating the Metadata structure of stream implementation in the Transforms and Hop Gui components, then review the format-mask work in issue #3120. The work is complete when metadata exposes currency, decimal-point, and thousand-grouping symbols for use by Metadata Injection.

Written by the indexing model from the issue text.