refactor(deepseek): convert dynamic import to static for handleOpenAIError

Replace dynamic `await import()` with a static import for `handleOpenAIError`
in the catch block, and update the error handler test to also assert the HTTP
status code (401) on the thrown error.

Signed-off-by: daewoongoh <dw.oh@samsung.com>

Author: daewoongoh

src/api/providers/__tests__/deepseek.spec.ts

@@ -431,7 +431,10 @@ describe("DeepSeekHandler", () => {
 			mockCreate.mockRejectedValueOnce(apiError)
 
 			const stream = handler.createMessage(systemPrompt, messages)
-			await expect(stream.next()).rejects.toThrow("DeepSeek completion error: Invalid API key")
+			const err = await stream.next().catch((e) => e)
+
+			expect(err.message).toBe("DeepSeek completion error: Invalid API key")
+			expect((err as any).status).toBe(401)
 		})
 
 		it("prefers delta.reasoning_content over delta.reasoning when both are present", async () => {

src/api/providers/deepseek.ts

@@ -18,6 +18,7 @@ import { convertToR1Format } from "../transform/r1-format"
 import { OpenAiHandler } from "./openai"
 import { extractReasoningFromDelta } from "./utils/extract-reasoning"
 import type { ApiHandlerCreateMessageMetadata } from "../index"
+import { handleOpenAIError } from "./utils/error-handler"
 
 // Custom interface for DeepSeek params to support thinking mode
 type DeepSeekChatCompletionParams = Omit<OpenAI.Chat.ChatCompletionCreateParamsStreaming, "reasoning_effort"> & {
@@ -137,7 +138,6 @@ export class DeepSeekHandler extends OpenAiHandler {
 				isAzureAiInference ? { path: OPENAI_AZURE_AI_INFERENCE_PATH } : {},
 			)
 		} catch (error) {
-			const { handleOpenAIError } = await import("./utils/error-handler")
 			throw handleOpenAIError(error, "DeepSeek")
 		}