[refactor] : AiClient 및 GitHostClient 인터페이스 추출

Author: Jwhyee

src/main/kotlin/com/project/codereview/domain/port/AiClient.kt

@@ -0,0 +1,12 @@
+package com.project.codereview.domain.port
+
+import com.project.codereview.domain.model.GeminiTextModel
+
+interface AiClient {
+    suspend fun chat(
+        filePath: String,
+        prompt: String,
+        model: GeminiTextModel,
+        systemPrompt: String
+    ): String?
+}

src/main/kotlin/com/project/codereview/domain/port/GitHostClient.kt

@@ -0,0 +1,9 @@
+package com.project.codereview.domain.port
+
+import com.project.codereview.domain.model.ReviewContext
+
+interface GitHostClient {
+    suspend fun addReviewSummaryComment(ctx: ReviewContext)
+    suspend fun addReviewComment(ctx: ReviewContext, review: String)
+    fun getPrDiff(owner: String, repo: String, prNumber: String): String
+}