feat: restructure market app with per-market URL scoping

- URL structure changes from /<route> to /<market_slug>/<route>
- Root / shows markets listing page
- app.py: url_value_preprocessor, url_defaults, hydrate_market (events app pattern)
- Browse queries (db_nav, db_products_nocounts, db_products_counts) accept market_id
- _productInfo reads g.market.id to scope all queries
- save_nav accepts market_id, sets on new NavTop rows
- API save_nav passes g.market.id
- Scraper default URLs point to /suma-market/ on port 8001

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

scrape/persist_snapshot/save_nav.py

@@ -19,7 +19,7 @@ async def save_nav(nav: Dict) -> None:
         await _save_nav(session, nav)
         await session.commit()
 
-async def _save_nav(session, nav: Dict) -> None:
+async def _save_nav(session, nav: Dict, market_id=None) -> None:
     print('===================SAVE NAV========================')
     print(nav)
     now = datetime.utcnow()
@@ -79,8 +79,10 @@ async def _save_nav(session, nav: Dict) -> None:
         if top:
             top.label = label
             top.deleted_at = None
+            if market_id is not None and top.market_id is None:
+                top.market_id = market_id
         else:
-            top = NavTop(label=label, slug=top_slug)
+            top = NavTop(label=label, slug=top_slug, market_id=market_id)
             session.add(top)
 
         await session.flush()