build: Remove vestigial kotlin-android plugin references for AGP 9

With AGP 9's built-in Kotlin, org.jetbrains.kotlin.android is no longer
applied to Android modules. Convention plugin hooks using
withPlugin("org.jetbrains.kotlin.android") were dead code — replaced
with withPlugin("com.android.application") and
withPlugin("com.android.library") which correctly trigger for
Android-only modules using built-in Kotlin.

- KoinConventionPlugin: split into app + library hooks
- AndroidRoomConventionPlugin: use com.android.library hook
- KotlinXSerializationConventionPlugin: use app + library hooks
- Remove kotlin-android from version catalog and root build.gradle.kts

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

build-logic/convention/src/main/kotlin/AndroidRoomConventionPlugin.kt

@@ -53,7 +53,7 @@ class AndroidRoomConventionPlugin : Plugin<Project> {
                 dependencies { add("kspJvm", roomCompiler) }
             }
 
-            pluginManager.withPlugin("org.jetbrains.kotlin.android") {
+            pluginManager.withPlugin("com.android.library") {
                 val hasAndroidTest = projectDir.resolve("src/androidTest").exists()
                 dependencies {
                     "implementation"(roomRuntime)

build-logic/convention/src/main/kotlin/KoinConventionPlugin.kt

@@ -48,7 +48,7 @@ class KoinConventionPlugin : Plugin<Project> {
                 }
             }
 
-            pluginManager.withPlugin("org.jetbrains.kotlin.android") {
+            pluginManager.withPlugin("com.android.application") {
                 // If this is *only* an Android module (no KMP plugin)
                 if (!pluginManager.hasPlugin("org.jetbrains.kotlin.multiplatform")) {
                     dependencies {
@@ -58,6 +58,16 @@ class KoinConventionPlugin : Plugin<Project> {
                 }
             }
 
+            pluginManager.withPlugin("com.android.library") {
+                // If this is *only* an Android library module (no KMP plugin)
+                if (!pluginManager.hasPlugin("org.jetbrains.kotlin.multiplatform")) {
+                    dependencies {
+                        add("implementation", koinCore)
+                        add("implementation", koinAnnotations)
+                    }
+                }
+            }
+
             pluginManager.withPlugin("org.jetbrains.kotlin.jvm") {
                 // If this is *only* a JVM module (no KMP plugin)
                 if (!pluginManager.hasPlugin("org.jetbrains.kotlin.multiplatform")) {

build-logic/convention/src/main/kotlin/KotlinXSerializationConventionPlugin.kt

@@ -36,10 +36,16 @@ class KotlinXSerializationConventionPlugin : Plugin<Project> {
                 }
             }
 
-            pluginManager.withPlugin("org.jetbrains.kotlin.android") {
+            pluginManager.withPlugin("com.android.application") {
                 dependencies { "implementation"(serializationLib) }
             }
 
+            pluginManager.withPlugin("com.android.library") {
+                if (!pluginManager.hasPlugin("org.jetbrains.kotlin.multiplatform")) {
+                    dependencies { "implementation"(serializationLib) }
+                }
+            }
+
             pluginManager.withPlugin("org.jetbrains.kotlin.jvm") { dependencies { "implementation"(serializationLib) } }
         }
     }

build.gradle.kts

@@ -26,7 +26,6 @@ plugins {
     alias(libs.plugins.firebase.crashlytics) apply false
     alias(libs.plugins.google.services) apply false
     alias(libs.plugins.room) apply false
-    alias(libs.plugins.kotlin.android) apply false
     alias(libs.plugins.kotlin.jvm) apply false
     alias(libs.plugins.kotlin.multiplatform) apply false
     alias(libs.plugins.kotlin.parcelize) apply false

gradle/libs.versions.toml

@@ -297,7 +297,6 @@ compose-screenshot = { id = "com.android.compose.screenshot", version.ref = "com
 compose-compiler = { id = "org.jetbrains.kotlin.plugin.compose", version.ref = "kotlin" }
 compose-multiplatform = { id = "org.jetbrains.compose", version.ref = "compose-multiplatform" }
 koin-compiler = { id = "io.insert-koin.compiler.plugin", version.ref = "koin-plugin" }
-kotlin-android = { id = "org.jetbrains.kotlin.android", version.ref = "kotlin" }
 kotlin-jvm = { id = "org.jetbrains.kotlin.jvm", version.ref = "kotlin" }
 kotlin-multiplatform = { id = "org.jetbrains.kotlin.multiplatform", version.ref = "kotlin" }
 kotlin-parcelize = { id = "org.jetbrains.kotlin.plugin.parcelize", version.ref = "kotlin" }