fix(android): pin build-tools to 36.0.0 for all modules

AGP 8.13 defaults to build-tools 35.0.0, but the provisioned / read-only CI SDK (/opt/android-sdk) has only 36.0.0 installed, so a gradle build (the app + the cap-sync-generated Capacitor modules) fails trying to auto-install 35 into a read-only dir. Pin buildToolsVersion 36.0.0 for every Android sub-project (compileSdk-matching) so the CI android-build signed release and local builds work. Verified: a local assembleDebug now builds app-debug.apk. ci.yaml does not build Android (only the manual android-build workflow does), so this is verified locally.

ui/android/build.gradle

@@ -24,6 +24,17 @@ allprojects {
     }
 }
 
+// Pin build-tools to the compileSdk-matching version for every Android module (the app + the
+// Capacitor modules regenerated by `cap sync`), so AGP does not fall back to its default (35.0.0),
+// which the provisioned / read-only CI SDK does not have installed.
+subprojects {
+    afterEvaluate {
+        if (project.hasProperty('android')) {
+            android.buildToolsVersion = "36.0.0"
+        }
+    }
+}
+
 task clean(type: Delete) {
     delete rootProject.buildDir
 }