flutterに関して環境構築中にエラー．．．助けてください

PS C:\Users\miyajima\StudioProjects\app> fvm flutter run --flavor dev
Launching lib\main.dart on sdk gphone64 x86 64 in debug mode...

FAILURE: Build failed with an exception.

* Where:
Settings file 'C:\Users\miyajima\StudioProjects\yattoruyo_app\android\settings.gradle' line: 2

* What went wrong:
Plugin [id: 'dev.flutter.flutter-plugin-loader', version: '1.0.0'] was not found in any of the following sources:

- Gradle Core Plugins (plugin is not in 'org.gradle' namespace)
- Included Builds (No included builds contain this plugin)
- Plugin Repositories (could not resolve plugin artifact 'dev.flutter.flutter-plugin-loader:dev.flutter.flutter-plugin-loader.gradle.plugin:1.0.0')
  Searched in the following repositories:
    Gradle Central Plugin Repository

* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights.
> Get more help at https://help.gradle.org.

BUILD FAILED in 813ms
Running Gradle task 'assembleDevDebug'...                          994ms
Error: Gradle task assembleDevDebug failed with exit code 1



または、問題・エラーが起きている画像をここにドラッグアンドドロップ

### 該当するソースコード
```言語名
dart

Launching lib\main.dart on sdk gphone64 x86 64 in debug mode...
e: file:///C:/Users/miyajima/StudioProjects/yattoruyo_app/android/app/src/main/kotlin/cc/sysad/yattoruyo_app/MainActivity.kt:3:8 Unresolved reference: io
e: file:///C:/Users/miyajima/StudioProjects/yattoruyo_app/android/app/src/main/kotlin/cc/sysad/yattoruyo_app/MainActivity.kt:5:21 Unresolved reference: FlutterActivity

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:compileDevDebugKotlin'.
> A failure occurred while executing org.jetbrains.kotlin.compilerRunner.GradleCompilerRunnerWithWorkers$GradleKotlinCompilerWorkAction
   > Compilation error. See log for more details

* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights.
> Get more help at https://help.gradle.org.

BUILD FAILED in 12s
Running Gradle task 'assembleDevDebug'...                          13.0s
Error: Gradle task assembleDevDebug failed with exit code 1

### 該当するソースコード
```言語名
dart

plugins {
    id "dev.flutter.flutter-plugin-loader" version "1.0.0"
    id "com.android.application" version "7.3.0" apply false
    id "com.google.gms.google-services" version "4.3.15" apply false
    id "org.jetbrains.kotlin.android" version "1.9.0" apply false
}

def localPropertiesFile = new File(rootProject.projectDir, "local.properties")
def properties = new Properties()

assert localPropertiesFile.exists()
localPropertiesFile.withReader("UTF-8") { reader -> properties.load(reader) }

def flutterSdkPath = properties.getProperty("flutter.sdk")
assert flutterSdkPath != null, "flutter.sdk not set in local.properties"
//apply from: "$flutterSdkPath/packages/flutter_tools/gradle/app_plugin_loader.gradle"
include ':app'

buildscript {
    ext.kotlin_version = '1.9.0'
    repositories {
        google()
        mavenCentral()
    }

    dependencies {
        classpath 'com.android.tools.build:gradle:8.7.2'
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
        classpath 'com.google.gms:google-services:4.3.2'
//        classpath 'com.google.firebase:firebase-crashlytics-gradle:2.9.9'
    }
}


allprojects {
    repositories {
        google()
        mavenCentral()
    }
}



rootProject.buildDir = '../build'
subprojects {
    project.buildDir = "${rootProject.buildDir}/${project.name}"
}
subprojects {
    project.evaluationDependsOn(':app')
}

tasks.register("clean", Delete) {
    delete rootProject.layout.buildDirectory
}

plugins {
    id 'com.android.application'
    id 'kotlin-android'
    id "dev.flutter.flutter-gradle-plugin"
    id 'com.google.gms.google-services'
    id 'com.google.firebase.crashlytics'

}


def localProperties = new Properties()
def localPropertiesFile = rootProject.file('local.properties')
if (localPropertiesFile.exists()) {
    localPropertiesFile.withReader('UTF-8') { reader ->
        localProperties.load(reader)
    }
}

def flutterRoot = localProperties.getProperty('flutter.sdk')
if (flutterRoot == null) {
    throw new FileNotFoundException("Flutter SDK not found. Define location with flutter.sdk in the local.properties file.")
}

def flutterVersionCode = localProperties.getProperty('flutter.versionCode')
if (flutterVersionCode == null) {
    flutterVersionCode = '1'
}

def flutterVersionName = localProperties.getProperty('flutter.versionName')
if (flutterVersionName == null) {
    flutterVersionName = '1.0'
}

def keystoreProperties = new Properties()
def keystorePropertiesFile = rootProject.file('key.properties')
if (keystorePropertiesFile.exists()) {
    keystoreProperties.load(new FileInputStream(keystorePropertiesFile))
}

//apply plugin: 'com.android.application'
//apply plugin: 'kotlin-android'
//apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"

android {
    namespace "cc.sysad.yattoruyo_app"
    compileSdkVersion 35

    sourceSets {
        main.java.srcDirs += 'src/main/kotlin'
    }

    defaultConfig {
        applicationId "cc.sysad.yattoruyo_app"
        minSdkVersion 24
        targetSdkVersion 35
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName
        multiDexEnabled true
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_17
        targetCompatibility JavaVersion.VERSION_17
    }

    kotlinOptions {
        jvmTarget = "17"
    }


    signingConfigs {
        release {
            keyAlias keystoreProperties['keyAlias']
            keyPassword keystoreProperties['keyPassword']
            storeFile keystoreProperties['storeFile'] ? file(keystoreProperties['storeFile']) : null
            storePassword keystoreProperties['storePassword']
        }

        develop {
            keyAlias keystoreProperties['keyAlias']
            keyPassword keystoreProperties['keyPassword']
            storeFile keystoreProperties['storeFile'] ? file(keystoreProperties['storeFile']) : null
            storePassword keystoreProperties['storePassword']        }
    }

    flavorDimensions "default"

    productFlavors {
        dev {
            dimension "default"
            applicationIdSuffix ".dev"
            versionNameSuffix ".dev"
            // アプリケーション名を変更したい場合
            resValue "string", "app_name", "(dev)"
            resValue "string", "facebook_app_id", ""
            resValue "string", "fb_login_protocol_scheme", ""
            manifestPlaceholders = [ applicationName: "io.flutter.app.FlutterApplication" ]
        }
        prod {
            dimension "default"
            // アプリケーション名を変更したい場合
            resValue "string", "app_name", ""
            resValue "string", "facebook_app_id", ""
            resValue "string", "fb_login_protocol_scheme", ""
            manifestPlaceholders = [ applicationName: "io.flutter.app.FlutterApplication" ]
        }
    }

    buildTypes {
        release {
            signingConfig signingConfigs.release
            signingConfig signingConfigs.debug
        }
    }
}

//flutter {
//    source '../..'
//}

dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
    implementation 'com.google.firebase:firebase-analytics:21.1.0'
    implementation 'com.google.firebase:firebase-crashlytics:18.2.11'
    implementation 'androidx.multidex:multidex:2.0.1'
    implementation "com.android.installreferrer:installreferrer:2.2"
}
//apply plugin: 'com.google.gms.google-services'
//apply plugin: 'com.google.firebase.crashlytics'

#Fri Jun 23 08:50:38 CEST 2017
distributionBase=GRADLE_USER_HOME
distributionPath=wrapper/dists
zipStoreBase=GRADLE_USER_HOME
zipStorePath=wrapper/dists
distributionUrl=https\://services.gradle.org/distributions/gradle-8.9-all.zip