build: remove browser configuration from core modules to fix JS plugin conflict

Eliminated `browser {}` blocks from core library modules to resolve "Plugin loaded multiple times" error in Kotlin/JS Gradle builds. Adjusted to support a cleaner, centralized JS target configuration. Documented the root cause and workaround in troubleshooting logs.

frontend/core/auth/build.gradle.kts

@@ -14,15 +14,9 @@ kotlin {
   jvm()
 
   js {
-    // browser {} block removed to avoid NodeJsRootPlugin conflicts in multi-module builds
-    // We only need explicit browser configuration in the shell (application) module.
-    // Tests are disabled via root build.gradle.kts configuration anyway.
-    nodejs {
-        testTask {
-            enabled = false
-        }
-    }
     binaries.library()
+    // browser {} block is intentionally removed to prevent "Plugin loaded multiple times" error.
+    // The warning "JS Environment Not Selected" is acceptable for now.
   }
 
   sourceSets {

frontend/core/design-system/build.gradle.kts

@@ -6,15 +6,10 @@ plugins {
 }
 
 kotlin {
-
   jvm()
-
   js(IR) {
     binaries.library()
-    // Explicitly select browser environment to satisfy Kotlin/JS compiler warning
-    browser {
-        testTask { enabled = false }
-    }
+    // browser {} block removed to fix "Plugin loaded multiple times" error.
   }
 
   sourceSets {

frontend/core/domain/build.gradle.kts

@@ -12,9 +12,7 @@ kotlin {
   jvm()
   js {
     binaries.library()
-    browser {
-        testTask { enabled = false }
-    }
+    // browser {} block removed to fix "Plugin loaded multiple times" error.
   }
 
   sourceSets {

frontend/core/local-db/build.gradle.kts

@@ -12,9 +12,7 @@ kotlin {
   jvm()
   js {
     binaries.library()
-    browser {
-        testTask { enabled = false }
-    }
+    // browser {} block removed to fix "Plugin loaded multiple times" error.
   }
 
   sourceSets {

frontend/core/navigation/build.gradle.kts

@@ -13,9 +13,7 @@ kotlin {
   jvm()
   js {
     binaries.library()
-    browser {
-        testTask { enabled = false }
-    }
+    // browser {} block removed to fix "Plugin loaded multiple times" error.
   }
 
   sourceSets {

frontend/core/network/build.gradle.kts

@@ -12,9 +12,7 @@ kotlin {
   jvm()
   js {
     binaries.library()
-    browser {
-        testTask { enabled = false }
-    }
+    // browser {} block removed to fix "Plugin loaded multiple times" error.
   }
 
   sourceSets {

frontend/core/sync/build.gradle.kts

@@ -7,16 +7,14 @@ kotlin {
   jvm()
   js(IR) {
     binaries.library()
-    browser {
-        testTask { enabled = false }
-    }
+    // browser {} block removed to fix "Plugin loaded multiple times" error.
   }
 
   sourceSets {
     commonMain.dependencies {
-      // Correct dependency: Syncable interface is in the shared core domain
+      // Correct dependency: Syncable interface is in shared core domain
       implementation(projects.core.coreDomain)
-      // Also include frontend domain if needed (e.g., for frontend-specific models)
+      // Also include frontend domain if needed (e.g. for frontend specific models)
       implementation(projects.frontend.core.domain)
 
       // Networking