ContactForm: Hide subject dropdown when only one contact is available

[Codencode]

Questions	Answers
Description?	When only one contact is available in the Contact Form module, the subject dropdown is no longer displayed. Instead of rendering a <select> with a single option, the module now automatically sets the id_contact value using a hidden input. This improves the user experience by removing an unnecessary selection while preserving the expected form behavior.
Type?	improvement
BC breaks?	no
Deprecations?	no
Fixed ticket?
How to test?	- In the admin panel, go to Shop Parameters > Contact - Delete the contacts, leaving only one - In the front office, go to the Contact page - The Subject Heading label and its related select dropdown should not be displayed NOTE: If you are using the classic theme, delete (or rename) the file themes/classic/modules/contactform/views/templates/widget/contactform.tpl. If you are using the hummingbird theme, do the same. This is essential to see the modification.
Related PRs	PrestaShop/hummingbird#932 PrestaShop/classic-theme#201

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Before

After

Note

If this PR is approved, I will update the modules/contactform/views/templates/widget/contactform.tpl file in both the classic and hummingbird themes accordingly.

[ps-jarvis]

Hello @Codencode!

This is your first pull request on contactform repository of the PrestaShop project.

Thank you, and welcome to this Open Source community!

[Touxten]

Logic

[Codencode]

@kpodemski
there's a compatibility issue with PHP here, similar to this other PR: PrestaShop/ps_socialfollow#51
However, my PR didn't touch the contactform.php file.
Fixing this issue is relatively simple, so do you think I should fix it? Or should we leave it as is?

Thanks

[tblivet]

Sorry, I didn’t see the question about the CI break!
Any thoughts on this? @kpodemski

all good

[Touxten]

Ok for CI it's for all native module