fix(ocr): address code review: add model fallback default, remove unused variable

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>

app/utils/text_quality.py

@@ -261,7 +261,7 @@ def check_text_quality(text: str, text_source: TextSource) -> TextQualityResult:
     response_text: Optional[str] = None
     try:
         provider = get_ai_provider()
-        model = settings.ai_model or settings.openai_model
+        model = settings.ai_model or settings.openai_model or "gpt-4o-mini"
         response_text = provider.chat_completion(
             messages=[
                 {

tests/test_text_quality.py

@@ -401,7 +401,6 @@ class TestCheckTextQualityAI:
 
         assert len(captured_prompts) == 1
         # The prompt should NOT contain more than _TEXT_SAMPLE_MAX_CHARS "a"s
-        count_a = captured_prompts[0].count("a" * 100)
         assert "a" * (_TEXT_SAMPLE_MAX_CHARS + 1) not in captured_prompts[0]