refactor: use module interface for empty module validation

Moved from AST checking to module interface, similar to what I did on publish.rs.

Also, previously the code counted public definitions from the AST and checked if the definitions list was empty. Now it directly checks if both the values and types HashMaps in the module interface are empty, as suggested by @GearsDatapacks

Author: vitorsouzaalmeida

compiler-core/src/build/package_compiler.rs

@@ -571,16 +571,13 @@ fn analyse(
                 let _ = module_types.insert(module.name.clone(), module.ast.type_info.clone());
 
                 // Check for empty modules and emit warning
-                let public_definitions = module
-                    .ast
-                    .definitions
-                    .iter()
-                    .filter(|def| def.is_public())
-                    .count();
-
                 // Only emit the empty module warning if the module has no definitions at all.
                 // Modules with only private definitions already emit their own warnings.
-                if public_definitions == 0 && module.ast.definitions.is_empty() {
+                if module_types
+                    .get(&module.name)
+                    .map(|interface| interface.values.is_empty() && interface.types.is_empty())
+                    .unwrap_or(false)
+                {
                     warnings.emit(crate::warning::Warning::EmptyModule {
                         path: module.input_path.clone(),
                         name: module.name.clone(),