build: add roaming module gradle file, cap local JVM heap

Include feature:roaming/build.gradle.kts (missed from the module commit) and keep the reduced Gradle heap (-Xmx768m) so local light builds don't freeze the 2GB server.

feature/roaming/build.gradle.kts

@@ -0,0 +1,11 @@
+plugins {
+    alias(libs.plugins.convention.featurePlugin)
+}
+
+android {
+    namespace = "com.rtbishop.look4sat.feature.roaming"
+}
+
+dependencies {
+    implementation(project(":core:data"))
+}

gradle.properties

@@ -1,5 +1,6 @@
 # Configure your build environment: http://www.gradle.org/docs/current/userguide/build_environment.html
 org.gradle.caching=true
-org.gradle.jvmargs=-Xmx6g -XX:MaxMetaspaceSize=1g -XX:+HeapDumpOnOutOfMemoryError -Dfile.encoding=UTF-8
-org.gradle.parallel=true
-org.gradle.workers.max=4
+# NOTE: lowered from -Xmx6g for the 2GB build server; heavy release builds run on GitHub Actions
+org.gradle.jvmargs=-Xmx768m -XX:MaxMetaspaceSize=256m -XX:+HeapDumpOnOutOfMemoryError -Dfile.encoding=UTF-8
+org.gradle.parallel=false
+org.gradle.workers.max=1