Address PR review: rename package to pw.binom.agui, add native KMP targets, fix native event serialization

- Rename module package com.agui -> pw.binom.agui (dirs + code + root group)
- Expand KMP targets on all modules: jvm + macOS/ios/Linux/mingw (no Android)
- Server native via ktor-server-cio; client native via ktor-client-cio
- Annotate sealed interface BaseEvent with @Serializable so the sealed
  serializer resolves without reflection on Kotlin/Native (was reflection-only
  on JVM, so native tests failed with 'Serializer for class BaseEvent not found')

client/build.gradle.kts

@@ -6,6 +6,14 @@ plugins {
 kotlin {
     jvmToolchain(21)
     jvm()
+    macosX64()
+    macosArm64()
+    iosX64()
+    iosArm64()
+    iosSimulatorArm64()
+    linuxX64()
+    linuxArm64()
+    mingwX64()
 
     sourceSets {
         commonMain.dependencies {
@@ -17,6 +25,9 @@ kotlin {
         jvmMain.dependencies {
             implementation(libs.ktor.client.cio)
         }
+        nativeMain.dependencies {
+            implementation(libs.ktor.client.cio)
+        }
         commonTest.dependencies {
             implementation(kotlin("test"))
         }

client/src/commonMain/kotlin/pw/binom/agui/client/HttpAgent.kt

@@ -1,9 +1,9 @@
-package com.agui.client
+package pw.binom.agui.client
 
-import com.agui.api.agent.Agent
-import com.agui.api.event.BaseEvent
-import com.agui.api.run.RunAgentInput
-import com.agui.api.serialization.AguiJson
+import pw.binom.agui.api.agent.Agent
+import pw.binom.agui.api.event.BaseEvent
+import pw.binom.agui.api.run.RunAgentInput
+import pw.binom.agui.api.serialization.AguiJson
 import io.ktor.client.HttpClient
 import io.ktor.client.plugins.sse.sse
 import io.ktor.client.request.setBody

client/src/jvmMain/kotlin/pw/binom/agui/client/HttpAgentFactory.kt

@@ -1,4 +1,4 @@
-package com.agui.client
+package pw.binom.agui.client
 
 import io.ktor.client.HttpClient
 import io.ktor.client.HttpClientConfig

client/src/jvmTest/kotlin/pw/binom/agui/client/HttpAgentTest.kt

@@ -1,15 +1,15 @@
-package com.agui.client
+package pw.binom.agui.client
 
-import com.agui.api.agent.Agent
-import com.agui.api.event.RunFinishedEvent
-import com.agui.api.event.RunStartedEvent
-import com.agui.api.event.TextMessageContentEvent
-import com.agui.api.event.TextMessageEndEvent
-import com.agui.api.event.TextMessageStartEvent
-import com.agui.api.message.Message
-import com.agui.api.message.MessageRole
-import com.agui.api.run.RunAgentInput
-import com.agui.server.agui
+import pw.binom.agui.api.agent.Agent
+import pw.binom.agui.api.event.RunFinishedEvent
+import pw.binom.agui.api.event.RunStartedEvent
+import pw.binom.agui.api.event.TextMessageContentEvent
+import pw.binom.agui.api.event.TextMessageEndEvent
+import pw.binom.agui.api.event.TextMessageStartEvent
+import pw.binom.agui.api.message.Message
+import pw.binom.agui.api.message.MessageRole
+import pw.binom.agui.api.run.RunAgentInput
+import pw.binom.agui.server.agui
 import io.ktor.client.plugins.sse.SSE
 import io.ktor.server.application.application
 import io.ktor.server.testing.testApplication
@@ -21,7 +21,7 @@ import kotlin.test.assertEquals
 import kotlin.test.assertIs
 
 /**
- * Exercises [HttpAgent] against the real AG-UI endpoint exposed by [com.agui.server.agui],
+ * Exercises [HttpAgent] against the real AG-UI endpoint exposed by [pw.binom.agui.server.agui],
  * using the Ktor test host so the SSE transport is exercised end-to-end over HTTP.
  */
 class HttpAgentTest {