fix(ai): retry Bun socket drops

closes #6431

packages/ai/test/retry.test.ts

@@ -6,6 +6,8 @@ const openAIExplicitRetryMessage =
 	"An error occurred while processing your request. You can retry your request, or contact us through our help center at help.openai.com if the error persists. Please include the request ID req_******** in your message.";
 const bedrockExplicitRetryMessage =
 	'{"message":"The system encountered an unexpected error during processing. Try your request again."}';
+const bunFetchSocketClosedMessage =
+	"The socket connection was closed unexpectedly. For more information, pass `verbose: true` in the second argument to fetch()";
 
 describe("provider retry classification", () => {
 	it("matches explicit provider retry guidance", () => {
@@ -21,6 +23,14 @@ describe("provider retry classification", () => {
 		).toBe(true);
 	});
 
+	it("matches Bun fetch socket drop wording", () => {
+		expect(
+			isRetryableAssistantError(
+				fauxAssistantMessage("", { stopReason: "error", errorMessage: bunFetchSocketClosedMessage }),
+			),
+		).toBe(true);
+	});
+
 	it("keeps provider limit errors non-retryable", () => {
 		expect(
 			isRetryableAssistantError(