feat: optional: resource contact may be chosen via a drop-down list of users

[JohnVillalovos]

Optional feature, that when changing the contact of a resource in the
Web UI, the contact must be chosen from a list of users on the system.

This is enabled via:
$conf['settings']['resource.contact.is.user'] = 'true';

[Copilot]

Pull Request Overview

This PR adds functionality to allow resource contacts to be selected from a dropdown list of registered users instead of free-form text entry. This provides better data validation and consistency for resource contact information.

• Added a configuration option to enable/disable user-based contact selection
• Modified the UI to show a dropdown for user selection when the feature is enabled
• Created a new autocomplete endpoint for user selection with formatted display

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tpl/Admin/Resources/manage_resources.tpl	Updates the contact field to conditionally use dropdown selection based on configuration
lib/Config/ConfigKeys.php	Adds new configuration key for enabling user-based contact selection
config/config.dist.php	Adds default configuration setting for the new feature
config/config.devel.php	Adds development configuration setting for the new feature
Pages/Ajax/AutoCompletePage.php	Implements new autocomplete endpoint for user selection with formatted output
Pages/Admin/ManageResourcesPage.php	Sets template variable based on configuration to control UI behavior

Comments suppressed due to low confidence (2)

Pages/Ajax/AutoCompletePage.php:194

• The class name 'XAutocompleteUser' is unclear. The 'X' prefix doesn't convey meaningful information about its purpose. Consider renaming to something more descriptive like 'FormattedAutocompleteUser' or 'AutocompleteUserOption'.

class XAutocompleteUser

Pages/Ajax/AutoCompletePage.php:233

• The constant name 'XUser' is unclear. The 'X' prefix doesn't convey meaningful information about its purpose. Consider renaming to something more descriptive like 'FormattedUser' to indicate it returns formatted user data.

    public const XUser = 'xuser';