Gradle, js, npm: fix reading package.json files

#KT-31788 Fixed

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/npm/NpmDependency.kt

@@ -46,6 +46,9 @@ data class NpmDependency(
 
             npmProject.resolve(item.key)?.let {
                 all.add(it)
+                if (it.path.endsWith(".js")) {
+                    all.add(File(it.path.removeSuffix(".js") + ".meta.js"))
+                }
             }
 
             if (transitive) {

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/npm/NpmProjectModules.kt

@@ -60,9 +60,9 @@ internal open class NpmProjectModules(
                 Gson().fromJson(it, JsonObject::class.java)
             }
 
-            packageJson["main"] as? String?
-                ?: packageJson["module"] as? String?
-                ?: packageJson["browser"] as? String?
+            packageJson.getStringOrNull("main")
+                ?: packageJson.getStringOrNull("module")
+                ?: packageJson.getStringOrNull("browser")
         } else null
 
         return if (main != null) {
@@ -72,6 +72,14 @@ internal open class NpmProjectModules(
         } else resolveIndex(dir)
     }
 
+    private fun JsonObject.getStringOrNull(key: String): String? {
+        val value = get(key)
+        if (value == null || !value.isJsonPrimitive) return null
+        val jsonPrimitive = value.asJsonPrimitive
+        if (jsonPrimitive.isString) return jsonPrimitive.asString
+        return null
+    }
+
     private fun resolveIndex(dir: File): File? = resolveAsFile(dir.resolve(INDEX_FILE_NAME))
 
     private fun resolveAsFile(file: File): File? {