Switch default LLM to Gemini Flash-Lite and fix SSE for Cloudflare

- Change default LLM from gpt-4o-mini to gemini-flash-lite across frontend and backend
- Replace SSE streaming with polling for Cloudflare Tunnel compatibility
- Add cache/buffering headers to SSE endpoint

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

formatter.py

@@ -587,7 +587,7 @@ def _truncate_text(text: str, max_chars: int = 100000) -> tuple:
 def format_as_markdown(
     text: str,
     title: str,
-    llm_provider: str = "gpt-4o-mini",
+    llm_provider: str = "gemini-flash-lite",
     api_key: Optional[str] = None,
     ollama_model: str = "llama3.2",
     on_progress: Optional[Callable] = None,
@@ -646,7 +646,7 @@ def format_as_markdown(
 def translate_text(
     text: str,
     target_lang: str,
-    llm_provider: str = "gpt-4o-mini",
+    llm_provider: str = "gemini-flash-lite",
     api_key: Optional[str] = None,
     ollama_model: str = "llama3.2",
     on_progress: Optional[Callable] = None,

templates/index.html

@@ -794,7 +794,7 @@
         let timerInterval = null;
         let startTime = null;
         let tipInterval = null;
-        let selectedLLM = 'gpt-4o-mini';
+        let selectedLLM = 'gemini-flash-lite';
         let llmModels = [];
         let languages = [];
         let llmLoaded = false;
@@ -1194,32 +1194,44 @@
                 }
 
                 const jobId = data.job_id;
-                const eventSource = new EventSource(`/api/stream/${jobId}`);
+                let pollSeen = 0;
+
+                const pollInterval = setInterval(async () => {
+                    try {
+                        const res = await fetch(`/api/status/${jobId}`);
+                        const job = await res.json();
+
+                        if (job.error && !job.progress) {
+                            clearInterval(pollInterval);
+                            stopTimer();
+                            showError(job.error);
+                            return;
+                        }
 
-                eventSource.onmessage = (event) => {
-                    const msg = JSON.parse(event.data);
+                        while (pollSeen < job.progress.length) {
+                            const msg = job.progress[pollSeen];
+                            if (msg.step && msg.percent !== undefined) {
+                                updateStep(msg.step, msg.percent, msg.detail || '');
+                            }
+                            pollSeen++;
+                        }
 
-                    if (msg.type === 'progress') {
-                        if (msg.step && msg.percent !== undefined) {
-                            updateStep(msg.step, msg.percent, msg.detail || '');
+                        if (job.status === 'completed') {
+                            clearInterval(pollInterval);
+                            stopTimer();
+                            setAllStepsDone();
+                            setTimeout(() => showResult(job.result), 500);
+                        } else if (job.status === 'error') {
+                            clearInterval(pollInterval);
+                            stopTimer();
+                            showError(job.error);
                         }
-                    } else if (msg.type === 'completed') {
-                        eventSource.close();
+                    } catch (err) {
+                        clearInterval(pollInterval);
                         stopTimer();
-                        setAllStepsDone();
-                        setTimeout(() => showResult(msg.result), 500);
-                    } else if (msg.type === 'error') {
-                        eventSource.close();
-                        stopTimer();
-                        showError(msg.message);
+                        showError('서버 연결이 끊어졌습니다. 서버가 실행 중인지 확인해주세요.');
                     }
-                };
-
-                eventSource.onerror = () => {
-                    eventSource.close();
-                    stopTimer();
-                    showError('서버 연결이 끊어졌습니다. 서버가 실행 중인지 확인해주세요.');
-                };
+                }, 1000);
             } catch (err) {
                 stopTimer();
                 showError(`요청 실패: ${err.message}`);

web.py

@@ -215,7 +215,15 @@ async def stream_status(job_id: str):
 
             await asyncio.sleep(0.5)
 
-    return StreamingResponse(event_generator(), media_type="text/event-stream")
+    return StreamingResponse(
+        event_generator(),
+        media_type="text/event-stream",
+        headers={
+            "Cache-Control": "no-cache",
+            "X-Accel-Buffering": "no",
+            "Connection": "keep-alive",
+        },
+    )
 
 
 @app.get("/api/download/{filename}")