feat: indiciate variables support on input field

[Julusian]

This is a pretty small change, that I think will help users. I am not 100% sold on the look, if anyone has ideas on how to improve it please do say

A simple indicator to show that the input field supports variables. On hover it shows Supports variables. It is using the useVariables property to decide to show this, which matches how we decide whether to suggest variables while typing.

I am hoping that we can add more icons to both this field type and others over time to indicate support for other features that modules need to implement support for

[MeestorX]

Can you also add this icon to dropdowns when allowCustom is enabled, as it allows for variables too.
Another request to PLEASE add variable support for ALL input types. Numbers, Checkboxes, etc.

[Julusian]

Can you also add this icon to dropdowns when allowCustom is enabled, as it allows for variables too.

Any suggestion on what icon should be used for allowCustom?

Another request to PLEASE add variable support for ALL input types. Numbers, Checkboxes, etc.

The architectural challenges blocking this don't have a solution yet

[MeestorX]

Can you also add this icon to dropdowns when allowCustom is enabled, as it allows for variables too.

Any suggestion on what icon should be used for allowCustom?

I think the same icon would be fine.

Another request to PLEASE add variable support for ALL input types. Numbers, Checkboxes, etc.

The architectural challenges blocking this don't have a solution yet

Copy that. NP.

[dnmeid]

@MeestorX your request is already on my todo list for a long time: #2345

[Julusian]

Can you also add this icon to dropdowns when allowCustom is enabled, as it allows for variables too.

Any suggestion on what icon should be used for allowCustom?

I think the same icon would be fine.

I'm not sure it should be the same, as there is no guarantee that allowCustom means that variables can be used.
But an allowVariables option could be added to the dropdowns to show that icon, with a different icon shown if it supports allowCustom, once we figure out what that icon should be