feat: 集成服务端驱动 UI 演示

新增 Remote Compose 播放端与服务端生成逻辑，支持按页面拉取并渲染二进制 UI 文档。

ComposeRemoteServer/src/main/java/com/ttstd/composeremote/server/controller/RemoteUIController.java

@@ -0,0 +1,33 @@
+package com.ttstd.composeremote.server.controller;
+
+import com.ttstd.composeremote.server.RemoteDocumentBuilderKt;
+import org.springframework.http.MediaType;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+/**
+ * 服务端驱动 UI 接口。
+ *
+ * <p>一个页面一个接口：每个页面通过独立的路径暴露，例如
+ * <ul>
+ *     <li>GET /api/remote-ui/home  → 首页</li>
+ *     <li>GET /api/remote-ui/detail → 详情页</li>
+ * </ul>
+ * 返回 {@code application/octet-stream} 的 Remote Compose 二进制文档，
+ * 由 Android 端 {@code RemoteComposePlayer} 原生渲染。
+ */
+@RestController
+@RequestMapping("/api/remote-ui")
+public class RemoteUIController {
+
+    @GetMapping(
+            value = {"/{page}", ""},
+            produces = MediaType.APPLICATION_OCTET_STREAM_VALUE
+    )
+    public byte[] getPage(@PathVariable(name = "page", required = false) String page) {
+        String target = (page == null || page.isBlank()) ? "home" : page;
+        return RemoteDocumentBuilderKt.buildRemoteDocument(target);
+    }
+}

ComposeRemoteServer/src/main/kotlin/com/ttstd/composeremote/server/RemoteDocumentBuilder.kt

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+package com.ttstd.composeremote.server
+
+import androidx.compose.remote.core.CoreDocument
+import androidx.compose.remote.creation.JvmRcPlatformServices
+import androidx.compose.remote.creation.RemoteComposeWriter
+import androidx.compose.remote.creation.dsl.RcColumnScope
+import androidx.compose.remote.creation.dsl.RcProfile
+import androidx.compose.remote.creation.dsl.RcSp
+import androidx.compose.remote.creation.dsl.createRcBuffer
+import androidx.compose.remote.creation.dsl.fillMaxSize
+import androidx.compose.remote.creation.dsl.fillMaxWidth
+import androidx.compose.remote.creation.dsl.padding
+import androidx.compose.remote.creation.dsl.background
+import androidx.compose.remote.creation.dsl.Modifier
+import androidx.compose.remote.creation.profile.Profile
+import androidx.compose.remote.creation.profile.RemoteComposeWriterFactory
+
+fun buildRemoteDocument(page: String): ByteArray {
+    val writerFactory = RemoteComposeWriterFactory { _, _, _ ->
+        RemoteComposeWriter(1080, 1920, "remote-ui", JvmRcPlatformServices())
+    }
+    val profile = Profile(
+        CoreDocument.DOCUMENT_API_LEVEL,
+        CoreDocument.PROFILE,
+        JvmRcPlatformServices(),
+        writerFactory
+    )
+    val rcProfile = RcProfile(profile, false)
+    return createRcBuffer(rcProfile) {
+        Column(Modifier.fillMaxSize().background(0xFFFFFFFF.toInt()).padding(16f)) {
+            Text(
+                text = if (page == "home") "Home Page" else "Detail Page",
+                fontSize = RcSp(36f),
+                color = 0xFF0000FF.toInt() // Blue
+            )
+        }
+    }
+}