feat(app): create MainActivity class, main activity

app/src/main/kotlin/com/intelligentbackpack/app/MainActivity.kt

@@ -0,0 +1,72 @@
+package com.intelligentbackpack.app
+
+import android.os.Bundle
+import androidx.activity.ComponentActivity
+import androidx.activity.compose.setContent
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.CompositionLocalProvider
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.tooling.preview.Preview
+import androidx.lifecycle.viewmodel.compose.LocalViewModelStoreOwner
+import androidx.navigation.compose.NavHost
+import androidx.navigation.compose.composable
+import androidx.navigation.compose.rememberNavController
+import androidx.navigation.navArgument
+import com.intelligentbackpack.app.ui.navigation.MainNavigation
+import com.intelligentbackpack.app.ui.theme.IntelligentBackpackAppTheme
+import com.intelligentbackpack.app.view.CreateUser
+import com.intelligentbackpack.app.view.Home
+import com.intelligentbackpack.app.view.Login
+
+class MainActivity : ComponentActivity() {
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContent {
+            val navController = rememberNavController()
+            val viewModelStoreOwner = LocalViewModelStoreOwner.current!!
+            IntelligentBackpackAppTheme {
+                Surface(
+                    modifier = Modifier.fillMaxSize(),
+                    color = MaterialTheme.colorScheme.background
+                ) {
+                    NavHost(navController, startDestination = MainNavigation.login) {
+
+                        composable(MainNavigation.login) {
+                            CompositionLocalProvider(
+                                LocalViewModelStoreOwner provides viewModelStoreOwner
+                            ) {
+                                Login(navController)
+                            }
+                        }
+                        composable(
+                            MainNavigation.createUser,
+                            arguments = listOf(navArgument(MainNavigation.createUserParam) { nullable = true })
+                        ) { backStackEntry ->
+                            val email = backStackEntry.arguments?.getString(MainNavigation.createUserParam)
+                            CompositionLocalProvider(
+                                LocalViewModelStoreOwner provides viewModelStoreOwner
+                            ) {
+                                CreateUser(
+                                    navController = navController,
+                                    email = email ?: "",
+                                )
+                            }
+
+                        }
+                        composable(MainNavigation.home) {
+                            CompositionLocalProvider(
+                                LocalViewModelStoreOwner provides viewModelStoreOwner
+                            ) {
+                                Home(navController = navController)
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+}