build: decouple app namespace from applicationId

Hardcoding `namespace = "org.fossify.messages"` in app/build.gradle.kts
lets a fork override `applicationId` (via gradle.properties APP_ID)
without rebasing the R class location and breaking thousands of
`org.fossify.messages.R` imports across the codebase.

No effect on the upstream build — applicationId still defaults to
APP_ID, only namespace stops following it.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

app/build.gradle.kts

@@ -116,7 +116,9 @@ android {
         )
     }
 
-    namespace = project.property("APP_ID").toString()
+    // Source-package namespace stays decoupled from applicationId so a fork
+    // can ship under its own ID without breaking thousands of `R` imports.
+    namespace = "org.fossify.messages"
 
     lint {
         checkReleaseBuilds = false
@@ -142,6 +144,7 @@ detekt {
 
 dependencies {
     implementation(libs.fossify.commons)
+    implementation(project(":translate"))
     implementation(libs.eventbus)
     implementation(libs.indicator.fast.scroll)
     implementation(libs.mmslib)