Script Loader: Warn when classic scripts depend on modules without footer/defer

[itzmekhokan]

Scripts registered or enqueued with a module_dependencies arg may evaluate before the script modules import map is printed if they are loaded blocking in the document head, causing a "Failed to resolve module specifier" error on dynamic imports.

Trigger _doing_it_wrong() from _wp_scripts_add_args_data() when a classic script provides module_dependencies without setting in_footer to true or using a defer loading strategy, and document this requirement in the wp_register_script() and wp_enqueue_script() docblocks.

Existing tests in wpScriptModules.php that exercised this path are updated to use in_footer => true so they continue to validate the import map behavior without tripping the new warning.

See #65165, #61500.

Trac ticket: https://core.trac.wordpress.org/ticket/65165

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