speed up android debug builds (#19335)

fixes #19081

## Summary
This PR aims to improve android build step for debug variants by ensuring we do not rebuild the android derivation for any change made to `clojurescript` code. 

We also do the following things : 
-  enable `JVM` parallel garbage collector.
-  get rid of `dexOptions` which was deprecated in `gradle 8`.
-  add additional `parallel` flag to `gradle` to speed up builds.

## Review notes
- `make run-clojure`
- `make run-android`
- ctrl + C on android terminal and edit any `cljs` file
- `make run-android`  ( should build almost instantly )

Author: siddarthkay

android/app/build.gradle

@@ -199,10 +199,6 @@ android {
         doNotStrip '*/mips/*.so'
         doNotStrip '*/mips64/*.so'
     }
-    dexOptions {
-        jumboMode true
-        javaMaxHeapSize "8g"
-    }
     splits {
         abi {
             reset()

android/build.gradle

@@ -44,6 +44,23 @@ subprojects {
                 defaultConfig {
                     targetSdkVersion rootProject.ext.targetSdkVersion
                 }
+
+                // Speed up Tests Stage
+                tasks.withType(Test).configureEach {
+                    // https://docs.gradle.org/current/userguide/performance.html#execute_tests_in_parallel
+                    maxParallelForks = Runtime.runtime.availableProcessors().intdiv(2) ?: 1
+                    // https://docs.gradle.org/current/userguide/performance.html#fork_tests_into_multiple_processes
+                    forkEvery = 100
+                    // https://docs.gradle.org/current/userguide/performance.html#disable_reports
+                    reports.html.required = false
+                    reports.junitXml.required = false
+                }
+                // Speed up Java Compile Stage
+                // https://docs.gradle.org/current/userguide/performance.html#run_the_compiler_as_a_separate_process
+                tasks.withType(JavaCompile).configureEach {
+                    options.fork = true
+                }
+
             }
         }
     }

android/gradle.properties

@@ -43,7 +43,7 @@ ANDROID_ABI_SPLIT=false
 # Some platforms are excluded though
 ANDROID_ABI_INCLUDE=armeabi-v7a;arm64-v8a;x86;x86_64
 
-org.gradle.jvmargs=-Xmx8704M
+org.gradle.jvmargs=-Xmx8704M -XX:+UseParallelGC
 
 versionCode=9999
 commitHash=unknown

nix/mobile/android/build.nix

@@ -26,9 +26,10 @@
 
 let
   inherit (lib) toLower optionalString stringLength makeLibraryPath elem;
+  notDebug = (buildType != "debug");
 
   # Pass secretsFile for POKT_TOKEN to jsbundle build
-  builtJsBundle = jsbundle { inherit secretsFile; };
+  builtJsBundle = lib.optionals notDebug jsbundle { inherit secretsFile; };
 
   # Map ANDROID_ABI_INCLUDE to status-go targets
   androidAbiIncludeSplit = lib.splitString ";" androidAbiInclude;
@@ -119,8 +120,10 @@ in stdenv.mkDerivation rec {
     # Export all vars from .env file
     export $(cut -d= -f1 .env)
 
+    ${lib.optionalString notDebug ''
     # Symlink React Native entrypoint.
     cp -Lr ${builtJsBundle} ./result
+    ''}
 
     # Copy android/ directory
     mkdir -p ./android/build
@@ -153,6 +156,7 @@ in stdenv.mkDerivation rec {
       --no-scan \
       --no-watch-fs \
       --no-build-cache \
+      --parallel \
       -Dmaven.repo.local='${deps.gradle}' \
       assemble${gradleBuildType}
     '';