feat: Implement core GitHub repository backup functionality

This commit introduces the foundational features for a GitHub repository backup application built with Compose for Desktop. It includes the data layer, presentation layer, and dependency injection setup.

-   **Data Layer & Repository:**
    -   Adds `GithubRepository` and its implementation (`GithubRepositoryImpl`) to handle interactions with the GitHub API.
    -   Implements `getRepositories` to fetch a user's repositories, handling pagination to retrieve all entries.
    -   Introduces `cloneRepository`, which uses `ProcessBuilder` to execute `git clone` commands, providing real-time progress updates by parsing the command's output.
    -   Defines data models (`GithubResponse`, `GitHubRepoItem`) for deserializing API responses.

-   **ViewModel & State Management:**
    -   Creates `RepoViewModel` to manage UI state (`RepoState`) and handle user intents (`RepoIntent`).
    -   Manages fetching repositories, selecting/deselecting items, searching/filtering, and orchestrating the download process.
    -   Calculates download progress, including total percentage and estimated time remaining (ETA).

-   **UI & Presentation:**
    -   Develops the main `RepoScreen` with a `Scaffold`, `TopAppBar`, and a custom `BottomBar`.
    -   Introduces components for user input (`GithubSelectionLayout`), repository listing (`RepoCard`), and user feedback (`ProgressDialog`, `ErrorDialog`).
    -   Implements a `LazyColumn` to display repositories with features like "Select All" and a search bar.
    -   Integrates custom `Filled` and `Outlined` buttons for consistent UI actions.
    -   Adds `AppTheme` with custom light and dark color schemes inspired by GitHub's design.

-   **Dependency Injection & Core Utilities:**
    -   Sets up Koin for dependency injection with dedicated modules for core services (`coreModule`), repositories (`repositoryModule`), and ViewModels (`viewModule`).
    -   Configures a Ktor `HttpClient` with JSON serialization, logging, and timeouts.
    -   Adds utility functions for file operations, logging (`AppLogger`), and system theme detection.

-   **Application Entry Point:**
    -   Updates `main.kt` to initialize Koin, `FileKit`, set up the main application window with a minimum size, and handle theme switching.

Author: Coding-Meet

composeApp/src/jvmMain/kotlin/com/meet/gitbackup/hub/App.kt

@@ -0,0 +1,42 @@
+package com.meet.gitbackup.hub.core.utility
+
+import co.touchlab.kermit.Logger
+import co.touchlab.kermit.StaticConfig
+import co.touchlab.kermit.platformLogWriter
+
+object AppLogger {
+
+    const val isDebugBuild = true
+
+    val logger = Logger(
+        config = StaticConfig(
+            logWriterList = if (isDebugBuild) {
+                listOf(platformLogWriter())
+            } else {
+                emptyList() // No logging in release
+            }
+        ),
+        tag = "Git-Backup-Hub"
+    )
+
+    inline fun d(tag: String = "", throwable: Throwable? = null, message: () -> String) {
+        if (isDebugBuild) {
+            logger.d(tag = tag, throwable = throwable, message = message)
+        }
+    }
+    inline fun i(tag: String = "", throwable: Throwable? = null, message: () -> String) {
+        if (isDebugBuild) {
+            logger.i(tag = tag, throwable = throwable, message = message)
+        }
+    }
+    inline fun e(tag: String = "", throwable: Throwable? = null, message: () -> String) {
+        if (isDebugBuild) {
+            logger.e(tag = tag, throwable = throwable, message = message)
+        }
+    }
+    inline fun w(tag: String = "", throwable: Throwable? = null, message: () -> String) {
+        if (isDebugBuild) {
+            logger.w(tag = tag, throwable = throwable, message = message)
+        }
+    }
+}

composeApp/src/jvmMain/kotlin/com/meet/gitbackup/hub/Greeting.kt

@@ -0,0 +1,5 @@
+package com.meet.gitbackup.hub.core.utility
+
+object Constant {
+
+}

composeApp/src/jvmMain/kotlin/com/meet/gitbackup/hub/Platform.kt

@@ -0,0 +1,52 @@
+package com.meet.gitbackup.hub.core.utility
+
+import io.ktor.client.HttpClient
+import io.ktor.client.engine.okhttp.OkHttp
+import io.ktor.client.plugins.HttpTimeout
+import io.ktor.client.plugins.contentnegotiation.ContentNegotiation
+import io.ktor.client.plugins.defaultRequest
+import io.ktor.client.plugins.logging.EMPTY
+import io.ktor.client.plugins.logging.LogLevel
+import io.ktor.client.plugins.logging.Logger
+import io.ktor.client.plugins.logging.Logging
+import io.ktor.http.ContentType
+import io.ktor.http.contentType
+import io.ktor.serialization.kotlinx.json.json
+import kotlinx.serialization.json.Json
+import kotlin.time.Duration.Companion.seconds
+
+
+object HttpClientFactory {
+    fun create(): HttpClient {
+        return HttpClient(
+            engine = OkHttp.create()
+        ) {
+            defaultRequest {
+                contentType(ContentType.Application.Json)
+            }
+            install(HttpTimeout) {
+                socketTimeoutMillis = 20.seconds.inWholeMilliseconds
+                requestTimeoutMillis = 20.seconds.inWholeMilliseconds
+            }
+            install(ContentNegotiation) {
+                json(Json {
+                    prettyPrint = true
+                    isLenient = true
+                    ignoreUnknownKeys = true
+                    explicitNulls = false
+                })
+            }
+            install(Logging) {
+                level = if (AppLogger.isDebugBuild) LogLevel.ALL else LogLevel.NONE
+                logger = if (AppLogger.isDebugBuild) object : Logger {
+                    override fun log(message: String) {
+                        AppLogger.d(tag = "KtorClient", null) {
+                            message
+                        }
+                    }
+                } else Logger.EMPTY
+            }
+
+        }
+    }
+}

composeApp/src/jvmMain/kotlin/com/meet/gitbackup/hub/core/utility/AppLogger.kt

@@ -0,0 +1,41 @@
+package com.meet.gitbackup.hub.core.utility
+
+import java.awt.Desktop
+import java.io.File
+
+
+object Utils {
+    fun File.openFile() {
+        if (Desktop.isDesktopSupported()) {
+            if (isDirectory) {
+                Desktop.getDesktop().open(this)
+            } else {
+                Desktop.getDesktop().open(parentFile)
+            }
+        }
+    }
+
+    fun String.openFile() {
+        val file = File(this)
+        file.openFile()
+    }
+    fun formatMillis(millis: Long): String {
+        val totalSeconds = millis / 1000
+        val minutes = totalSeconds / 60
+        val seconds = totalSeconds % 60
+        return if (minutes > 0) "${minutes}m ${seconds}s" else "${seconds}s"
+    }
+    fun tagName(
+        javaClass: Class<*>
+    ): String {
+        return if (!javaClass.isAnonymousClass) {
+            val name = javaClass.simpleName
+            if (name.length <= 23) name else name.substring(0, 23)  // first 23 chars
+        } else {
+            val name = javaClass.name
+            if (name.length <= 23) name else name.substring(
+                name.length - 23, name.length
+            )                   // last 23 chars
+        }
+    }
+}

composeApp/src/jvmMain/kotlin/com/meet/gitbackup/hub/core/utility/Constant.kt

@@ -0,0 +1,56 @@
+package com.meet.gitbackup.hub.core.utility
+
+import androidx.compose.runtime.Composable
+import androidx.compose.foundation.isSystemInDarkTheme
+import androidx.compose.runtime.DisposableEffect
+import androidx.compose.runtime.derivedStateOf
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.saveable.rememberSaveable
+import androidx.compose.runtime.setValue
+import com.jthemedetecor.OsThemeDetector
+import java.util.function.Consumer
+
+@Composable
+fun isSystemInDarkThemeMode(): Boolean {
+    val detector by remember {
+        mutableStateOf(
+            OsThemeDetector.getDetector()
+        )
+    }
+    val isSupported by remember(detector) {
+        derivedStateOf {
+            OsThemeDetector.isSupported()
+        }
+    }
+    val isDark by remember(detector.isDark) {
+        derivedStateOf {
+            detector.isDark
+        }
+    }
+    val isSystemThemeByFoundationLib = isSystemInDarkTheme()
+
+    var isSystemInDarkTheme by rememberSaveable(isDark,isSystemThemeByFoundationLib) {
+        mutableStateOf(
+            if (isSupported) {
+                detector.isDark
+            } else {
+                isSystemThemeByFoundationLib
+            }
+        )
+    }
+
+    DisposableEffect(isSystemInDarkTheme) {
+        val listener = Consumer<Boolean> {
+            if (isSupported) {
+                isSystemInDarkTheme = it
+            }
+        }
+        detector.registerListener(listener)
+        onDispose {
+            detector.removeListener(listener)
+        }
+    }
+    return isSystemInDarkTheme
+}

composeApp/src/jvmMain/kotlin/com/meet/gitbackup/hub/core/utility/HttpClientFactory.kt

@@ -0,0 +1,28 @@
+package com.meet.gitbackup.hub.data.models
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+import kotlin.uuid.ExperimentalUuidApi
+import kotlin.uuid.Uuid
+
+@Serializable
+data class GithubResponse(
+    @SerialName("total_count")
+    val totalCount: Int,
+    val items: List<GitHubRepoItem>
+)
+@OptIn(ExperimentalUuidApi::class)
+@Serializable
+data class GitHubRepoItem(
+    val uniqueId : String = Uuid.random().toString(),
+    val name: String,
+    @SerialName("clone_url")
+    val cloneUrl: String,
+    val description: String? = null,
+    @SerialName("default_branch")
+    val defaultBranch: String = "main",
+    val private: Boolean = false,
+    @SerialName("stargazers_count")
+    val stargazersCount: Int = 0,
+    val language: String? = null,
+)

composeApp/src/jvmMain/kotlin/com/meet/gitbackup/hub/core/utility/Utils.kt

@@ -0,0 +1,13 @@
+package com.meet.gitbackup.hub.data.repository
+
+import com.meet.gitbackup.hub.data.models.GitHubRepoItem
+
+interface GithubRepository {
+    suspend fun getRepositories(username: String, token: String?): List<GitHubRepoItem>
+
+    suspend fun cloneRepository(
+        repo: GitHubRepoItem, basePath: String, token: String?,
+        onProgress: (Int, String) -> Unit
+    )
+}
+