refactor(folio): build AppGraph from platform entry points

MainActivity (Android) and MainViewController (iOS) now own the
suspend DriverFactory.create() and feed the resulting LedgerDatabase
into Metro's createGraphFactory<AppGraph.Factory>().

examples/folio/app/androidApp/src/main/kotlin/app/folio/MainActivity.kt

@@ -4,11 +4,17 @@ import android.os.Bundle
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
 import app.folio.core.data.DriverFactory
+import app.folio.db.LedgerDatabase
+import app.folio.di.AppGraph
+import dev.zacsweers.metro.createGraphFactory
 
 class MainActivity : ComponentActivity() {
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         val driverFactory = DriverFactory(applicationContext)
-        setContent { App(driverFactory) }
+        val graphFactory = createGraphFactory<AppGraph.Factory>()
+        setContent {
+            App(graphBuilder = { graphFactory.create(LedgerDatabase(driverFactory.create())) })
+        }
     }
 }

examples/folio/app/shared/src/iosMain/kotlin/app/folio/MainViewController.kt

@@ -2,7 +2,10 @@ package app.folio
 
 import androidx.compose.ui.window.ComposeUIViewController
 import app.folio.core.data.DriverFactory
+import app.folio.db.LedgerDatabase
+import app.folio.di.AppGraph
 import app.folio.ui.IosBackGesture
+import dev.zacsweers.metro.createGraphFactory
 import kotlinx.cinterop.BetaInteropApi
 import kotlinx.cinterop.ExperimentalForeignApi
 import kotlinx.cinterop.ObjCAction
@@ -28,7 +31,10 @@ private val backGestureTarget = BackGestureTarget()
 @OptIn(ExperimentalForeignApi::class)
 fun MainViewController(): UIViewController {
     val driverFactory = DriverFactory()
-    val vc = ComposeUIViewController { App(driverFactory) }
+    val graphFactory = createGraphFactory<AppGraph.Factory>()
+    val vc = ComposeUIViewController {
+        App(graphBuilder = { graphFactory.create(LedgerDatabase(driverFactory.create())) })
+    }
     val gesture = UIScreenEdgePanGestureRecognizer(
         target = backGestureTarget,
         action = NSSelectorFromString("handleGesture:"),