Money - create new Civi:: facade - now format helper

Our CRM_Utils_Money class wound up a mess so we talked about creating a new supported/tested/readable class to put our money functions in and this class would be supported for use by core & external code.

@seamuslee did a first cut here https://github.com/civicrm/civicrm-core/pull/20296 which highlighted some of the issues / complexity

I made comments there but I've moved them to this gitlab

Useful framing by @jaapjansma

CiviCRM has the following ways of displaying data:

• On the screen in back office (this is the language and locale of the logged in user)
• On the screen in front office screens (such as registering for an event, this should be the sites locale and language)
• In communications with the contact, such as letters and pdf. We should use the language and locale of the contact Ideally we should also have a setting for the locale and not only the language.

Looking at @jaapjansma's list it seems that at the end of the day we want (these don't have to be all working / added now but I think we might want to comment in the intent into the class)

Money()->formatMachine($amount, $currency);
Money()->formatSiteLocale($amount, $currency);
Money()->formatUserLocale($amount, $currency, $contactID); // defaults to logged in user
Money()->formatSpecifiedLocale($amount, $currency, $locale);

We also have 2 other variables in the mix - precision & noCurrencySymbol

I tend to prefer to use separate functions for noCurrencySymbol - eg

Money()->formatNumericOnlyMachine($amount, $currency);
Money()->formatNumericOnlySiteLocale($amount, $currency);
Money()->formatNumericOnlyUserLocale($amount, $currency, $contactID); // defaults to logged in user
Money()->formatNumericOnlySpecifiedLocale($amount, $currency, $locale);

but it could be a consistent parameter in the other functions

On the precision question we have

• fixed precision
• no rounding
• currency specific precision

Perhaps this is a parameter on all the above functions ('fixed', NULL or 'by_currency' ) - I personally prefer documenting that in the comment block than using a constant although some people like constants

This is quickly getting us back into the confusion of CRM_Core_Money which this PR was intended to get us away from but hopefully we can figure out the set of signatures we want this time AND remember what they actually mean!

Also - we probably want functions that returns the actual Money object - not just the output

Note that where we want to be is that the CRM_Utils_Money class can be an internal class and the Civi::Money is an external class - so how we deal with the thousand separator in CRM_Utils_Money can change over time