chore: move Android SDK constants from buildSrc to version catalog

Replace Android.kt (buildSrc) with android-compileSdk, android-minSdk,
android-targetSdk, and android-java entries in libs.versions.toml.

This makes the values accessible from both build-logic convention
plugins and module build scripts, eliminating the duplicate hardcoded
values in AndroidLibraryConventionPlugin.

Author: bmc08gt

apps/flipcash/app/build.gradle.kts

@@ -30,15 +30,15 @@ val appNamespace = "${Gradle.flipcashNamespace}.app.android"
 android {
     // static namespace
     namespace = appNamespace
-    compileSdk = Android.compileSdkVersion
+    compileSdk = libs.versions.android.compileSdk.get().toInt()
 
     defaultConfig {
         versionCode = Packaging.Flipcash.versionCode ?: gitVersionCode()
         versionName = Packaging.Flipcash.versionName
         applicationId = appNamespace
-        minSdk = Android.minSdkVersion
-        targetSdk = Android.targetSdkVersion
-        testInstrumentationRunner = Android.testInstrumentationRunner
+        minSdk = libs.versions.android.minSdk.get().toInt()
+        targetSdk = libs.versions.android.targetSdk.get().toInt()
+        testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
 
         buildConfigField("String", "VERSION_NAME", "\"${Packaging.Flipcash.versionName}\"")
         buildConfigField("String", "MIXPANEL_API_KEY", "\"${tryReadProperty(rootProject.rootDir, "MIXPANEL_API_KEY")}\"")
@@ -65,6 +65,7 @@ android {
     buildTypes {
         getByName("release") {
             resValue("string", "applicationId", appNamespace)
+            signingConfig = signingConfigs.getByName("contributors")
             isMinifyEnabled = true
             isShrinkResources = true
             proguardFiles(getDefaultProguardFile("proguard-android-optimize.txt"), "proguard-rules.pro")
@@ -87,8 +88,8 @@ android {
     }
 
     compileOptions {
-        sourceCompatibility(Android.javaVersion)
-        targetCompatibility(Android.javaVersion)
+        sourceCompatibility(libs.versions.android.java.get())
+        targetCompatibility(libs.versions.android.java.get())
         isCoreLibraryDesugaringEnabled = true
     }
 
@@ -120,11 +121,11 @@ bugsnag {
 
 kotlin {
     jvmToolchain {
-        languageVersion.set(JavaLanguageVersion.of(Android.javaVersion))
+        languageVersion.set(JavaLanguageVersion.of(libs.versions.android.java.get()))
     }
 
     compilerOptions {
-        jvmTarget.set(JvmTarget.fromTarget(Android.javaVersion))
+        jvmTarget.set(JvmTarget.fromTarget(libs.versions.android.java.get()))
         optIn.addAll(
             "kotlin.time.ExperimentalTime",
             "kotlin.ExperimentalUnsignedTypes",

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

@@ -21,11 +21,16 @@ class AndroidLibraryConventionPlugin : Plugin<Project> {
                 }
             }
 
+            val libs = extensions.getByType<VersionCatalogsExtension>().named("libs")
+            val compileSdkVersion = libs.findVersion("android-compileSdk").get().requiredVersion.toInt()
+            val minSdkVersion = libs.findVersion("android-minSdk").get().requiredVersion.toInt()
+            val javaVersion = libs.findVersion("android-java").get().requiredVersion
+
             extensions.configure<LibraryExtension> {
-                compileSdk = 37
+                compileSdk = compileSdkVersion
 
                 defaultConfig {
-                    minSdk = 29
+                    minSdk = minSdkVersion
                     testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
                 }
 
@@ -34,18 +39,18 @@ class AndroidLibraryConventionPlugin : Plugin<Project> {
                 }
 
                 compileOptions {
-                    sourceCompatibility = JavaVersion.VERSION_21
-                    targetCompatibility = JavaVersion.VERSION_21
+                    sourceCompatibility = JavaVersion.toVersion(javaVersion)
+                    targetCompatibility = JavaVersion.toVersion(javaVersion)
                 }
             }
 
             extensions.configure<KotlinAndroidProjectExtension> {
                 jvmToolchain {
-                    languageVersion.set(JavaLanguageVersion.of(21))
+                    languageVersion.set(JavaLanguageVersion.of(javaVersion))
                 }
 
                 compilerOptions {
-                    jvmTarget.set(JvmTarget.JVM_21)
+                    jvmTarget.set(JvmTarget.fromTarget(javaVersion))
                     optIn.addAll(
                         "kotlin.time.ExperimentalTime",
                         "kotlin.ExperimentalUnsignedTypes",
@@ -54,8 +59,6 @@ class AndroidLibraryConventionPlugin : Plugin<Project> {
                 }
             }
 
-            val libs = extensions.getByType<VersionCatalogsExtension>().named("libs")
-
             dependencies {
                 "implementation"(libs.findLibrary("timber").get())
                 "implementation"(libs.findLibrary("kotlinx-coroutines-core").get())

buildSrc/src/main/java/Android.kt

@@ -1,4 +1,9 @@
 [versions]
+android-compileSdk = "37"
+android-minSdk = "29"
+android-targetSdk = "37"
+android-java = "21"
+
 kotlin = "2.3.21"
 ksp = "2.3.7"
 kotlinx-coroutines = "1.11.0"

gradle/libs.versions.toml

@@ -104,11 +104,11 @@ println "OpenCV: " +openCVersionName + " " + project.buildscript.sourceFile
 
 android {
     namespace 'org.opencv'
-    compileSdkVersion Android.compileSdkVersion
+    compileSdkVersion libs.versions.android.compileSdk.get().toInteger()
 
     defaultConfig {
-        minSdkVersion Android.minSdkVersion
-        targetSdkVersion Android.targetSdkVersion
+        minSdkVersion libs.versions.android.minSdk.get().toInteger()
+        targetSdkVersion libs.versions.android.targetSdk.get().toInteger()
 
 
         externalNativeBuild {
@@ -125,8 +125,8 @@ android {
         }
     }
     compileOptions {
-        sourceCompatibility(Android.javaVersion)
-        targetCompatibility(Android.javaVersion)
+        sourceCompatibility(libs.versions.android.java.get())
+        targetCompatibility(libs.versions.android.java.get())
     }
 
     buildTypes {