feat(01-04): add Koin + Kermit bootstrap commonMain + iOS bridge

- Add initKoin(config) helper wrapping startKoin { modules(appModule) } (PITFALL #4 single entry)
- Add empty appModule placeholder (D-14) — Phase 2+ extends
- Add configureLogging() setting Kermit tag "recipe" (D-15)
- Add iosMain doInitKoin() bridge — Swift-accessible as KoinIosKt.doInitKoin()
- configureLogging() always runs before initKoin() so module loading can log

composeApp/src/commonMain/kotlin/dev/ulfrx/recipe/di/AppModule.kt

@@ -0,0 +1,8 @@
+package dev.ulfrx.recipe.di
+
+import org.koin.dsl.module
+
+// Phase 2 adds authModule; Phase 4 adds syncModule; Phase 5 adds catalogModule; etc.
+val appModule = module {
+    // intentionally empty in Phase 1
+}

composeApp/src/commonMain/kotlin/dev/ulfrx/recipe/di/Koin.kt

@@ -0,0 +1,10 @@
+package dev.ulfrx.recipe.di
+
+import org.koin.core.KoinApplication
+import org.koin.core.context.startKoin
+import org.koin.dsl.KoinAppDeclaration
+
+fun initKoin(config: KoinAppDeclaration? = null): KoinApplication = startKoin {
+    config?.invoke(this)
+    modules(appModule)
+}

composeApp/src/commonMain/kotlin/dev/ulfrx/recipe/logging/Logging.kt

@@ -0,0 +1,8 @@
+package dev.ulfrx.recipe.logging
+
+import co.touchlab.kermit.Logger
+
+fun configureLogging() {
+    Logger.setTag("recipe")
+    // Platform log writers (OSLog iOS, LogCat Android, System.out JVM/Wasm) install by default.
+}