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/iosMain/kotlin/dev/ulfrx/recipe/di/KoinIos.kt

@@ -0,0 +1,8 @@
+package dev.ulfrx.recipe.di
+
+import dev.ulfrx.recipe.logging.configureLogging
+
+fun doInitKoin() {
+    configureLogging()
+    initKoin()
+}