feat: redesign Android app with animations, charts, profile, and registration

- Register screen with validation (username, email, password, confirm)
- Profile screen with email editing and password change
- User greeting on dashboard showing logged-in username
- 401 auto-logout via SessionManager + AuthInterceptor
- MetricsChart with Canvas line graphs (CPU, RAM, Disk)
- Animated StatCard with counters and icons
- ServerCard with progress bars, pulsating status dot, dynamic elevation
- Shimmer loading placeholders
- Dark mode support with Material3
- Navigation transitions (slide + fade)
- New server rack launcher icon
- Splash screen
- Backend API: register, profile (GET/PUT) endpoints

android/app/build.gradle.kts

@@ -0,0 +1,69 @@
+plugins {
+    id("com.android.application")
+    id("org.jetbrains.kotlin.plugin.compose")
+    id("org.jetbrains.kotlin.plugin.serialization")
+}
+
+android {
+    namespace = "com.devlab.app"
+    compileSdk = 37
+
+    defaultConfig {
+        applicationId = "com.devlab.app"
+        minSdk = 26
+        targetSdk = 37
+        versionCode = 1
+        versionName = "1.0.0"
+    }
+
+    buildTypes {
+        release {
+            isMinifyEnabled = false
+            proguardFiles(
+                getDefaultProguardFile("proguard-android-optimize.txt"),
+                "proguard-rules.pro"
+            )
+        }
+    }
+
+    compileOptions {
+        sourceCompatibility = JavaVersion.VERSION_17
+        targetCompatibility = JavaVersion.VERSION_17
+    }
+
+    buildFeatures {
+        compose = true
+    }
+}
+
+dependencies {
+    val composeBom = platform("androidx.compose:compose-bom:2026.05.01")
+    implementation(composeBom)
+
+    implementation("androidx.compose.ui:ui")
+    implementation("androidx.compose.ui:ui-graphics")
+    implementation("androidx.compose.ui:ui-tooling-preview")
+    implementation("androidx.compose.material3:material3")
+    implementation("androidx.compose.material:material-icons-extended")
+
+    implementation("androidx.core:core-ktx:1.19.0")
+    implementation("androidx.lifecycle:lifecycle-runtime-ktx:2.10.0")
+    implementation("androidx.lifecycle:lifecycle-viewmodel-compose:2.10.0")
+    implementation("androidx.activity:activity-compose:1.13.0")
+
+    implementation("androidx.navigation:navigation-compose:2.9.8")
+
+    implementation("com.squareup.retrofit2:retrofit:2.11.0")
+    implementation("com.squareup.retrofit2:converter-kotlinx-serialization:2.11.0")
+    implementation("com.squareup.okhttp3:okhttp:4.12.0")
+    implementation("com.squareup.okhttp3:logging-interceptor:4.12.0")
+
+    implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.8.0")
+
+    implementation("androidx.datastore:datastore-preferences:1.1.3")
+
+    implementation("androidx.core:core-splashscreen:1.0.1")
+
+    debugImplementation("androidx.compose.ui:ui-tooling")
+    debugImplementation("androidx.compose.ui:ui-test-manifest")
+}