feat(insta-lab): main.py — trends + preferences endpoints

- POST /api/insta/trends/collect — background trend collection via trend_collector.collect_all
- GET /api/insta/trends — list external trends with source/category/days filters
- GET /api/insta/preferences — return category weights (defaults seeded on init_db)
- PUT /api/insta/preferences — upsert category weights
- Modified GET /api/insta/keywords to accept source= filter (source present → list_trends, else existing list_trending_keywords, backward compatible)

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

insta-lab/app/main.py

@@ -15,7 +15,7 @@ from .config import (
     CORS_ALLOW_ORIGINS, NAVER_CLIENT_ID, ANTHROPIC_API_KEY,
     INSTA_DATA_PATH, DB_PATH, DEFAULT_CATEGORY_SEEDS, KEYWORDS_PER_CATEGORY,
 )
-from . import db, news_collector, keyword_extractor, card_writer, card_renderer
+from . import db, news_collector, keyword_extractor, card_writer, card_renderer, trend_collector
 
 logger = logging.getLogger(__name__)
 app = FastAPI()
@@ -119,7 +119,13 @@ def extract_keywords(req: ExtractRequest, bg: BackgroundTasks):
 
 
 @app.get("/api/insta/keywords")
-def list_keywords(category: Optional[str] = None, used: Optional[bool] = None):
+def list_keywords(
+    category: Optional[str] = None,
+    used: Optional[bool] = None,
+    source: Optional[str] = None,
+):
+    if source:
+        return {"items": db.list_trends(source=source, category=category, days=30)}
     return {"items": db.list_trending_keywords(category=category, used=used)}
 
 
@@ -243,3 +249,52 @@ def get_prompt(name: str):
 def upsert_prompt(name: str, body: TemplateBody):
     db.upsert_prompt_template(name, body.template, body.description)
     return db.get_prompt_template(name)
+
+
+# ── Trends ───────────────────────────────────────────────────────
+class TrendsCollectRequest(BaseModel):
+    categories: Optional[list[str]] = None
+
+
+async def _bg_collect_trends(task_id: str, categories: list[str]):
+    try:
+        db.update_task(task_id, "processing", 10, "외부 트렌드 수집 중")
+        result = trend_collector.collect_all(categories)
+        msg = f"naver:{result['naver_popular']}, google:{result['google_trends']}"
+        db.update_task(task_id, "succeeded", 100, msg, result_id=sum(result.values()))
+    except Exception as e:
+        logger.exception("trends collect failed")
+        db.update_task(task_id, "failed", 0, "", error=str(e))
+
+
+@app.post("/api/insta/trends/collect")
+def collect_trends(req: TrendsCollectRequest, bg: BackgroundTasks):
+    cats = req.categories or list(DEFAULT_CATEGORY_SEEDS.keys())
+    tid = db.create_task("trends_collect", {"categories": cats})
+    bg.add_task(_bg_collect_trends, tid, cats)
+    return {"task_id": tid, "categories": cats}
+
+
+@app.get("/api/insta/trends")
+def list_trends_endpoint(
+    source: Optional[str] = None,
+    category: Optional[str] = None,
+    days: int = Query(1, ge=1, le=90),
+):
+    return {"items": db.list_trends(source=source, category=category, days=days)}
+
+
+# ── Preferences ──────────────────────────────────────────────────
+class PreferencesBody(BaseModel):
+    categories: dict[str, float]
+
+
+@app.get("/api/insta/preferences")
+def get_preferences_endpoint():
+    return {"categories": db.get_preferences()}
+
+
+@app.put("/api/insta/preferences")
+def put_preferences_endpoint(body: PreferencesBody):
+    db.upsert_preferences(body.categories)
+    return {"categories": db.get_preferences()}