Enable Gradle build and configuration caching (#8669)

Enabling `org.gradle.caching` allows Gradle to reuse task outputs from
previous builds, significantly reducing build times for incremental
builds. Enabling `org.gradle.configuration-cache` caches the result of
the configuration phase, skipping the evaluation of the build script
when no configuration changes are detected.

These optimizations reduced local build verification time from ~1m 7s to
~46s.

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Author: jwren

gradle.properties

@@ -13,3 +13,6 @@ javaVersion=21
 kotlin.stdlib.default.dependency=false
 org.gradle.parallel=true
 org.gradle.jvmargs=-Xms1024m -Xmx4048m
+
+org.gradle.caching=true
+org.gradle.configuration-cache=true