fix: improve type safety for max_completion_tokens params

Remove Record<string, unknown> type annotation to let TypeScript infer
the params object type, preserving type checking on all properties.
Cast to ChatCompletionCreateParamsNonStreaming at the create() call site
to accommodate the SDK's missing max_completion_tokens type. Add unit
test for reasoning model detection regex.

Signed-off-by: majiayu000 <1835304752@qq.com>

src/engine/openAi.ts

@@ -45,16 +45,16 @@ export class OpenAiEngine implements AiEngine {
   ): Promise<string | null> => {
     const isReasoningModel = /^(o[1-9]|gpt-5)/.test(this.config.model);
 
-    const params: Record<string, unknown> = {
+    const params = {
       model: this.config.model,
       messages,
       ...(isReasoningModel
         ? { max_completion_tokens: this.config.maxTokensOutput }
         : {
-            temperature: 0,
-            top_p: 0.1,
-            max_tokens: this.config.maxTokensOutput
-          })
+          temperature: 0,
+          top_p: 0.1,
+          max_tokens: this.config.maxTokensOutput
+        })
     };
 
     try {
@@ -68,7 +68,9 @@ export class OpenAiEngine implements AiEngine {
       )
         throw new Error(GenerateCommitMessageErrorEnum.tooMuchTokens);
 
-      const completion = await this.client.chat.completions.create(params);
+      const completion = await this.client.chat.completions.create(
+        params as OpenAI.Chat.Completions.ChatCompletionCreateParamsNonStreaming
+      );
 
       const message = completion.choices[0].message;
       let content = message?.content;