fix(amazonq): Q infers source file from active test file for UTG. (#5356)

* Show the source file path instead of test file path in short answer if user does /test on test file.

Author: laileni-aws

.changes/next-release/bugfix-62042604-3335-445b-90f6-d6f688087c9d.json

@@ -0,0 +1,4 @@
+{
+  "type" : "bugfix",
+  "description" : "Amazon Q /test: Q identify active test file and infer source file for test generation."
+}

plugins/amazonq/chat/jetbrains-community/src/software/aws/toolkits/jetbrains/services/amazonqCodeTest/CodeWhispererUTGChatManager.kt

@@ -59,6 +59,7 @@ import java.io.ByteArrayInputStream
 import java.io.ByteArrayOutputStream
 import java.io.File
 import java.io.IOException
+import java.nio.file.Path
 import java.nio.file.Paths
 import java.time.Duration
 import java.time.Instant
@@ -249,9 +250,10 @@ class CodeWhispererUTGChatManager(val project: Project, private val cs: Coroutin
                     if (shortAnswer.stopIteration == "true") {
                         throw CodeTestException("TestGenFailedError: ${shortAnswer.planSummary}", "TestGenFailedError", shortAnswer.planSummary)
                     }
+                    val fileName = shortAnswer.sourceFilePath?.let { Path.of(it).fileName.toString() } ?: path.fileName.toString()
                     codeTestChatHelper.updateAnswer(
                         CodeTestChatMessageContent(
-                            message = generateSummaryMessage(path.fileName.toString()) + shortAnswer.planSummary,
+                            message = generateSummaryMessage(fileName) + shortAnswer.planSummary,
                             type = ChatMessageType.Answer
                         ),
                         messageIdOverride = codeTestResponseContext.testSummaryMessageId