feat: Implement "About" screen

This commit introduces a new "About" screen that displays application information, including version, development team credits, and other acknowledgments.

**Key Changes:**

*   **feat(AboutScreen):**
    *   Added a new `AboutScreen.kt` Composable to display app logo, version, development team roles, and other details.
    *   Created modular `InfoSection` and `InfoItem` components to structure the content.
    *   The screen features a top app bar with a back button.

*   **feat(Navigation):**
    *   Added a new `Screen.About` destination to the navigation graph.
    *   The "About" option in the `UserScreen` now navigates to the newly created `AboutScreen`.

app/src/main/java/com/qingshuige/tangyuan/App.kt

@@ -20,6 +20,7 @@ import com.qingshuige.tangyuan.navigation.Screen
 import com.qingshuige.tangyuan.ui.components.PageLevel
 import com.qingshuige.tangyuan.ui.components.TangyuanBottomAppBar
 import com.qingshuige.tangyuan.ui.components.TangyuanTopBar
+import com.qingshuige.tangyuan.ui.screens.AboutScreen
 import com.qingshuige.tangyuan.ui.screens.PostDetailScreen
 import com.qingshuige.tangyuan.ui.screens.ImageDetailScreen
 import com.qingshuige.tangyuan.ui.screens.TalkScreen
@@ -50,6 +51,7 @@ fun App() {
                     onAuthorClick = { authorId ->
                         navController.navigate(Screen.UserDetail.createRoute(authorId))
                     },
+                    onAboutClick = { navController.navigate(Screen.About.route) },
                     sharedTransitionScope = this@SharedTransitionLayout,
                     animatedContentScope = this@composable
                 )
@@ -169,6 +171,12 @@ fun App() {
                     animatedContentScope = this@composable
                 )
             }
+
+            composable(Screen.About.route) {
+                AboutScreen(
+                    onBackClick = { navController.popBackStack() }
+                )
+            }
         }
     }
 }
@@ -180,6 +188,7 @@ fun MainFlow(
     onPostClick: (Int) -> Unit,
     onImageClick: (Int, Int) -> Unit = { _, _ -> },
     onAuthorClick: (Int) -> Unit = {},
+    onAboutClick: () -> Unit,
     sharedTransitionScope: SharedTransitionScope? = null,
     animatedContentScope: AnimatedContentScope? = null,
     userViewModel: UserViewModel = hiltViewModel()
@@ -269,9 +278,7 @@ fun MainFlow(
                     onSettings = {
                         // TODO: 导航到设置页面
                     },
-                    onAbout = {
+                    onAbout = onAboutClick
-                        // TODO: 导航到关于页面
-                    }
                 )
             }
         }

app/src/main/java/com/qingshuige/tangyuan/navigation/Screen.kt

@@ -6,6 +6,7 @@ sealed class Screen(val route: String, val title: String) {
     object Topic : Screen("topic", "侃一侃")
     object Message : Screen("message", "消息")
     object User : Screen("settings", "我的")
+    object About : Screen("about", "关于")
     object PostDetail : Screen("post_detail/{postId}", "帖子详情") {
         fun createRoute(postId: Int) = "post_detail/$postId"
     }

app/src/main/java/com/qingshuige/tangyuan/ui/screens/AboutScreen.kt

@@ -0,0 +1,206 @@
+package com.qingshuige.tangyuan.ui.screens
+
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.ColumnScope
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.verticalScroll
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.ArrowBack
+import androidx.compose.material.icons.filled.MoreVert
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Scaffold
+import androidx.compose.material3.Surface
+import androidx.compose.material3.Text
+import androidx.compose.material3.TopAppBar
+import androidx.compose.material3.TopAppBarDefaults
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.res.painterResource
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.tooling.preview.Preview
+import androidx.compose.ui.unit.dp
+import com.qingshuige.tangyuan.R
+import com.qingshuige.tangyuan.ui.components.AuroraBackground
+import com.qingshuige.tangyuan.ui.theme.LiteraryFontFamily
+import com.qingshuige.tangyuan.ui.theme.TangyuanGeneralFontFamily
+import com.qingshuige.tangyuan.ui.theme.TangyuanTheme
+
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+fun AboutScreen(
+    onBackClick: () -> Unit = {}
+) {
+
+    Scaffold(topBar = {
+        TopAppBar(
+            title = {
+                Text(
+                    text = "关于",
+                    style = MaterialTheme.typography.titleMedium,
+                    fontWeight = FontWeight.Bold,
+                    modifier = Modifier.fillMaxWidth(),
+                    textAlign = TextAlign.Center
+                )
+            },
+            navigationIcon = {
+                IconButton(onClick = onBackClick) {
+                    Icon(
+                        imageVector = Icons.Default.ArrowBack,
+                        contentDescription = "返回",
+                        tint = MaterialTheme.colorScheme.onSurface
+                    )
+                }
+            },
+            actions = {
+                IconButton(onClick = {}) {
+                    Icon(
+                        imageVector = Icons.Default.MoreVert,
+                        contentDescription = "其他",
+                        tint = MaterialTheme.colorScheme.onSurface
+                    )
+                }
+            },
+            colors = TopAppBarDefaults.topAppBarColors(
+                containerColor = MaterialTheme.colorScheme.surfaceVariant
+            ),
+            modifier = Modifier.fillMaxWidth()
+        )
+    }) { contentPadding ->
+        AuroraBackground {
+            Column(
+                modifier = Modifier
+                    .fillMaxSize()
+                    .verticalScroll(rememberScrollState())
+                    .padding(contentPadding),
+                horizontalAlignment = Alignment.CenterHorizontally
+            ) {
+                // App Logo and Name
+                Spacer(modifier = Modifier.height(32.dp))
+                Icon(
+                    painter = painterResource(R.drawable.ic_launcher_foreground),
+                    contentDescription = "App Logo",
+                    modifier = Modifier.size(100.dp),
+                    tint = MaterialTheme.colorScheme.primary
+                )
+                Spacer(modifier = Modifier.height(16.dp))
+                Text(
+                    text = "糖原",
+                    style = MaterialTheme.typography.headlineMedium.copy(
+                        fontWeight = FontWeight.Bold,
+                        fontFamily = LiteraryFontFamily
+                    )
+                )
+                Text(
+                    text = "Version 1.0.0", // Placeholder
+                    style = MaterialTheme.typography.bodyMedium,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant
+                )
+                Spacer(modifier = Modifier.height(48.dp))
+
+                // Info Sections
+                InfoSection(title = "开发团队") {
+                    InfoItem(label = "Lead Developer", value = "线粒体 XianliticCN")
+                    InfoItem(label = "Algorithm", value = "南木, 浩瀚之渺, Legend")
+                    InfoItem(label = "Business Manager", value = "なかのみく")
+                    InfoItem(label = "Test", value = "NukeCirno, 嘉木, 猕猴桃教教主")
+                    Spacer(modifier = Modifier.height(8.dp))
+                    Text(
+                        text = "所有成员皆参与了开发过程的全部工作。",
+                        style = MaterialTheme.typography.bodySmall,
+                        color = MaterialTheme.colorScheme.onSurfaceVariant,
+                        textAlign = TextAlign.Center,
+                        modifier = Modifier.padding(horizontal = 16.dp)
+                    )
+                }
+
+                InfoSection(title = "Logo 设计") {
+                    InfoItem(value = "南木")
+                }
+
+                InfoSection(title = "代号设计") {
+                    InfoItem(value = "NukeCirno")
+                }
+
+                InfoSection(title = "特别纪念") {
+                    Text(
+                        text = "糖原在一台序列号为 6a34145e 的小米5上完成调试。",
+                        style = MaterialTheme.typography.bodyMedium,
+                        color = MaterialTheme.colorScheme.onSurfaceVariant,
+                        textAlign = TextAlign.Center,
+                        modifier = Modifier.padding(horizontal = 16.dp)
+                    )
+                }
+                Spacer(modifier = Modifier.height(32.dp))
+            }
+        }
+    }
+}
+
+@Composable
+private fun InfoSection(
+    title: String,
+    content: @Composable ColumnScope.() -> Unit
+) {
+    Column(
+        modifier = Modifier
+            .fillMaxWidth()
+            .padding(vertical = 12.dp),
+        horizontalAlignment = Alignment.CenterHorizontally
+    ) {
+        Text(
+            text = title,
+            style = MaterialTheme.typography.titleLarge,
+            fontFamily = TangyuanGeneralFontFamily,
+            fontWeight = FontWeight.Bold,
+            modifier = Modifier.padding(bottom = 8.dp)
+        )
+        Column(
+            horizontalAlignment = Alignment.CenterHorizontally,
+            content = content
+        )
+    }
+}
+
+@Composable
+private fun InfoItem(label: String? = null, value: String) {
+    Row(
+        modifier = Modifier.padding(vertical = 4.dp),
+        verticalAlignment = Alignment.CenterVertically
+    ) {
+        if (label != null) {
+            Text(
+                text = "$label: ",
+                style = MaterialTheme.typography.bodyMedium,
+                fontWeight = FontWeight.Bold,
+                color = MaterialTheme.colorScheme.onSurface
+            )
+        }
+        Text(
+            text = value,
+            style = MaterialTheme.typography.bodyMedium,
+            color = MaterialTheme.colorScheme.onSurfaceVariant
+        )
+    }
+}
+
+@Preview(showBackground = true)
+@Composable
+fun AboutScreenPreview() {
+    TangyuanTheme {
+        Surface {
+            AboutScreen()
+        }
+    }
+}