fix: add missing thinkingBlockOpen to AnthropicStreamState in tests

The AnthropicStreamState type requires thinkingBlockOpen but the test
objects at lines 250 and 350 were missing it, causing TS2741 errors.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: BlueSkyXN

tests/anthropic-response.test.ts

@@ -251,6 +251,7 @@ describe("OpenAI to Anthropic Streaming Response Translation", () => {
       messageStartSent: false,
       contentBlockIndex: 0,
       contentBlockOpen: false,
+      thinkingBlockOpen: false,
       toolCalls: {},
     }
     const translatedStream = openAIStream.flatMap((chunk) =>
@@ -351,6 +352,7 @@ describe("OpenAI to Anthropic Streaming Response Translation", () => {
       messageStartSent: false,
       contentBlockIndex: 0,
       contentBlockOpen: false,
+      thinkingBlockOpen: false,
       toolCalls: {},
     }
     const translatedStream = openAIStream.flatMap((chunk) =>