fix: fork under own applicationId com.rtbishop.look4sat.bg7nta

The official app signs com.rtbishop.look4sat with its own certificate. A fork sharing that applicationId cannot be installed over the official build (signature mismatch) and users saw overwrite/install failures.

- Add applicationId version catalog entry; namespace stays com.rtbishop.look4sat so source imports are untouched, applicationId becomes com.rtbishop.look4sat.bg7nta.
- Update PROPERTY_SATELLITE_DATA_OPTIMIZED meta-data to the fork id.
- Document the fork-applicationId requirement in the version catalog.

build-logic/convention/src/main/java/com/rtbishop/look4sat/convention/PluginSetupUtils.kt

@@ -57,7 +57,7 @@ internal fun Project.setupAndroidApp() {
         namespace = libs.versions.packageName.get()
         compileSdk = libs.versions.compileSdk.get().toInt()
         defaultConfig {
-            applicationId = libs.versions.packageName.get()
+            applicationId = libs.versions.applicationId.get()
             minSdk = libs.versions.minSdk.get().toInt()
             versionCode = libs.versions.appVersionCode.get().toInt()
             versionName = libs.versions.appVersionName.get()