Standalone Shonar Desktop: vendor portable sources + local engine; decouple from ~/Projects/Shonar

- shared/ = portable Android-origin sources vendored from deferred/desktop-server
  (app/build.gradle.kts srcDir repointed; PlaybackController.kt excluded as Android-only)
- backend/ = bundled-lite engine (SQLite + inline queue); .venv symlinked from the
  old checkout, PYTHONPATH pins THIS backend's code over any editable install
- repoRoot() resolves this project dir (env SHONAR_REPO still wins); desktop-dev.sh
  watches shared/ + backend/
- Verified: :app:compileKotlin + :app:test green (23 tests); engine boots on :8010,
  self-migrates, /healthz ok

app/build.gradle.kts

@@ -0,0 +1,99 @@
+plugins {
+    kotlin("jvm") version "2.0.21"
+    id("org.jetbrains.kotlin.plugin.compose") version "2.0.21"
+    id("org.jetbrains.compose") version "1.7.3"
+}
+
+group = "com.shonar"
+version = "0.1.0"
+
+repositories {
+    mavenCentral()
+    google()
+}
+
+kotlin {
+    jvmToolchain(17)
+}
+
+sourceSets {
+    main {
+        kotlin {
+            // Portable shared sources vendored into this project (formerly
+            // compiled in place from the sibling Android repo). Android-only
+            // files excluded below.
+            srcDir("../shared")
+            exclude(
+                "com/shonar/ShonarApplication.kt",
+                "com/shonar/MainActivity.kt",
+                // settings store impls are Android (DataStore/Keystore);
+                // desktop provides its own (desktopSettingsStore.kt).
+                "com/shonar/settings/SettingsStore.kt",
+                // recording: only AiContent.kt is portable.
+                "com/shonar/recording/MigrationRunner.kt",
+                "com/shonar/recording/RecordingDao.kt",
+                "com/shonar/recording/RecordingEntity.kt",
+                "com/shonar/recording/RecordingNotificationHelper.kt",
+                "com/shonar/recording/PlaybackController.kt",
+                "com/shonar/recording/RecordingPermissionHelper.kt",
+                "com/shonar/recording/RecordingRepository.kt",
+                "com/shonar/recording/RecordingService.kt",
+                "com/shonar/recording/RecordingStateStore.kt",
+                "com/shonar/recording/ShonarDatabase.kt",
+                "com/shonar/recording/SyncDrain.kt",
+                "com/shonar/recording/SyncSlots.kt",
+                "com/shonar/recording/SyncStateConverter.kt",
+                "com/shonar/recording/SyncWorker.kt",
+                // widget + rename-after-save UI: Android-only (AppWidget,
+                // ShonarApplication references).
+                "com/shonar/widget/**",
+                "com/shonar/ui/rename/**",
+                // ui: only ui/folder/FolderList.kt is portable.
+                "com/shonar/ui/detail/**",
+                "com/shonar/ui/home/**",
+                "com/shonar/ui/provider/**",
+                "com/shonar/ui/settings/**",
+                "com/shonar/ui/theme/**",
+                "com/shonar/ui/folder/FolderBrowserScreen.kt",
+            )
+            srcDir("src/main/kotlin")
+        }
+    }
+    test {
+        kotlin {
+            srcDir("src/test/kotlin")
+        }
+    }
+}
+
+dependencies {
+    implementation(compose.desktop.currentOs)
+    implementation(compose.material3)
+    implementation(compose.materialIconsExtended)
+    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-swing:1.9.0")
+    implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.7.3")
+    implementation("com.squareup.okhttp3:okhttp:4.12.0")
+    // Real org.json for JVM (Android stubs throw "not mocked").
+    implementation("org.json:json:20240303")
+
+    testImplementation("junit:junit:4.13.2")
+    testImplementation("org.jetbrains.kotlinx:kotlinx-coroutines-test:1.9.0")
+    testImplementation("com.squareup.okhttp3:mockwebserver:4.12.0")
+}
+
+compose.desktop {
+    application {
+        mainClass = "com.shonar.desktop.MainKt"
+        nativeDistributions {
+            targetFormats(org.jetbrains.compose.desktop.application.dsl.TargetFormat.Dmg)
+            targetFormats(org.jetbrains.compose.desktop.application.dsl.TargetFormat.Msi)
+            targetFormats(org.jetbrains.compose.desktop.application.dsl.TargetFormat.Deb)
+            packageName = "shonar-desktop"
+            packageVersion = "0.1.0"
+        }
+    }
+}
+
+tasks.withType<Test> {
+    useJUnit()
+}