build: add release signing config and Zapstore publish config

- release signing reads keystore/keystore.properties (git-ignored)
- zapstore.yaml publishes the app via local APK source

.gitignore

@@ -7,3 +7,4 @@ local.properties
 /captures
 .externalNativeBuild
 .cxx
+keystore/

app/build.gradle.kts

@@ -3,6 +3,14 @@ plugins {
     id("org.jetbrains.kotlin.android")
 }
 
+import java.util.Properties
+
+val keystoreProperties = Properties()
+val keystorePropertiesFile = rootProject.file("keystore/keystore.properties")
+if (keystorePropertiesFile.exists()) {
+    keystoreProperties.load(keystorePropertiesFile.inputStream())
+}
+
 android {
     namespace = "lostmyphone.app"
     compileSdk = 34
@@ -15,9 +23,21 @@ android {
         versionName = "1.0"
     }
 
+    signingConfigs {
+        if (keystorePropertiesFile.exists()) {
+            create("release") {
+                storeFile = rootProject.file(keystoreProperties.getProperty("storeFile"))
+                storePassword = keystoreProperties.getProperty("storePassword")
+                keyAlias = keystoreProperties.getProperty("keyAlias")
+                keyPassword = keystoreProperties.getProperty("keyPassword")
+            }
+        }
+    }
+
     buildTypes {
         release {
             isMinifyEnabled = false
+            signingConfig = signingConfigs.findByName("release")
             proguardFiles(
                 getDefaultProguardFile("proguard-android-optimize.txt"),
                 "proguard-rules.pro"

zapstore.yaml

@@ -0,0 +1,13 @@
+# Zapstore publishing config
+# See https://zapstore.dev/docs/publish for details.
+repository: https://git.atitlan.io/avi/lost-my-phone
+pubkey: npub1x0wx48ceselh57fxda3yy0vcrcmawy22clm5djrlgq93ywg4zlaqdjt4ed
+release_source: ./app/build/outputs/apk/release/app-release.apk
+
+name: Lost My Phone
+description: >-
+  An Android app that listens for SMS commands to trigger a loud ring,
+  overriding Do Not Disturb, so you can find your phone.
+summary: Find your phone with an SMS trigger that cuts through Do Not Disturb.
+tags: [android, sms, ring, alarm, find-my-phone, dnd]
+license: MIT