Add Smarty4 folder

[eileenmcnaughton]

I tried out smarty4& it looks like it's a small step from Smarty3 to Smarty4 but a bit trickier to Smarty5 until we get rid of Smarty2

I think it makes sense to add Smarty4 to our vendor dir to try out in the same way as Smarty3 & when we hard switch my recent testing suggests 4 rather than 3 makes sense

[civibot]

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[eileenmcnaughton]

test this please

[eileenmcnaughton]

test this please

[colemanw]

Why are we doing this in civicrm-packages instead of civicrm-core/composer.json?

[demeritcowboy]

Probably because then the autoloader will pick it up even if you haven't enabled smarty 4.

[colemanw]

Ok