enhance: read Sentry DSN from local.properties to support private configuration

androidApp/build.gradle.kts

@@ -1,4 +1,5 @@
 import org.jetbrains.kotlin.gradle.dsl.JvmTarget
+import java.util.Properties
 
 plugins {
     alias(libs.plugins.androidApplication)
@@ -50,6 +51,10 @@ android {
                 .toInt()
         versionCode = 1
         versionName = "1.0.0-alpha01"
+
+        // Crash-reporting DSN, kept out of the public repo: read from local.properties
+        // (glitchtip.dsn=...). Empty when absent, which disables the Sentry SDK.
+        manifestPlaceholders["glitchtipDsn"] = localProperty("glitchtip.dsn") ?: ""
     }
     packaging {
         resources {
@@ -67,3 +72,12 @@ android {
         targetCompatibility = JavaVersion.VERSION_11
     }
 }
+
+/** Reads a key from the root local.properties, or null when the file or key is absent. */
+fun localProperty(key: String): String? {
+    val file = rootProject.file("local.properties")
+    if (!file.exists()) return null
+    return Properties()
+        .apply { file.inputStream().use { load(it) } }
+        .getProperty(key)
+}

androidApp/src/main/AndroidManifest.xml

@@ -21,7 +21,8 @@
             </intent-filter>
         </activity>
 
-        <meta-data android:name="io.sentry.dsn" android:value="https://c7d665816e7f4823aa48c083b797e730@eu.glitchtip.com/255" />
+        <!-- Injected from local.properties (glitchtip.dsn); an empty DSN disables the SDK. -->
+        <meta-data android:name="io.sentry.dsn" android:value="${glitchtipDsn}" />
         <meta-data android:name="io.sentry.traces.sample-rate" android:value="0.01" />
 
     </application>