feat(chat): add sse dependency and chat data models

app/build.gradle.kts

@@ -67,6 +67,7 @@ dependencies {
     implementation("org.mozilla.geckoview:geckoview-omni:115.0.20230710165010")
     implementation("com.google.android.material:material:1.12.0")
     implementation("com.squareup.okhttp3:okhttp:4.12.0")
+    implementation("com.squareup.okhttp3:okhttp-sse:4.12.0")
     implementation("com.github.getActivity:XXPermissions:18.2")
     implementation(libs.androidx.appcompat)
     implementation(libs.androidx.core.ktx)

app/src/main/java/com/stand/standapp/ui/chat/model/ChatModels.kt

@@ -0,0 +1,21 @@
+package com.stand.standapp.ui.chat.model
+
+import java.util.UUID
+
+data class ChatSession(
+    val id: String = UUID.randomUUID().toString(),
+    val title: String = "新对话",
+    val timestamp: Long = System.currentTimeMillis()
+)
+
+data class ChatMessage(
+    val id: String = UUID.randomUUID().toString(),
+    val sessionId: String,
+    val role: Role,
+    val content: String,
+    val isStreaming: Boolean = false
+) {
+    enum class Role {
+        USER, AI
+    }
+}