Optimize products list analytics loading

CONTEXT.md

@@ -73,6 +73,10 @@ This project (often referred to as "Nexstar Graphs" or simply "Graphs") is a rea
 *   **Campaign Observability:** The frontend has a `Campanhas` page backed by `/api/campaigns`, `/api/campaigns/preview`, `/api/campaigns/process`, and `/api/campaigns/retry`.
 *   **WhatsApp Marketing Integration:** The system extracts phone numbers from incoming n8n payloads (checking `Fone_Cliente`, `fone`, or `celular`). Numbers are exposed in the UI for direct "Click-to-Chat" links and exported to CSV files.
 *   **Filter Persistence:** User preferences for Date Ranges, Sort options, and Auto-Refresh intervals are persisted to `localStorage` to survive page reloads.
+*   **RFV Segmentation:** The Portuguese UI calls customer segmentation **RFV** (`Recência`, `Frequência`, `Valor`). Internal code/API names may still use `rfm` to avoid route/type churn. The visible app labels should use RFV.
+*   **RFV Date Semantics:** Date filters use local calendar-day boundaries and send stable `YYYY-MM-DD` query params. Backend analytics treats `start` and `end` as inclusive `data_pedido_date` bounds.
+*   **RFV Tag Aggregation Rule:** RFV is not recalculated from only the selected period. For a selected period, the backend first calculates each buyer's RFV tag using history **before the period starts**. It then aggregates only the purchases inside the selected period by that prior tag. Example: if a client was `Champions` before today and buys today, `Champions` gets +1 client and that period revenue. If an `Em Risco` client does not buy today, `Em Risco` does not get counted for today's filter.
+*   **RFV Display Rule:** The RFV table's `Última Compra` date is the purchase date inside the selected period. Date-only strings must be parsed as local dates in the frontend to avoid UTC shifting (`2026-06-15` must render as `15/06/2026`, not `14/06/2026`). The small recency text below it displays `Hoje`, `Ontem`, or `X dias` relative to the selected range end.
 
 ## 6. CI/CD & Deployment
 *   **Gitea Actions:** A workflow located in `.gitea/workflows/deploy.yml` triggers on pushes to the `main` branch.
@@ -110,6 +114,11 @@ cd backend
 npm test
 ```
 
+**Frontend Date/RFV Helper Test:**
+```bash
+node --experimental-strip-types --test src/dateRanges.test.ts
+```
+
 **Persistent Local Stack:**
 ```bash
 docker compose up -d --build
@@ -124,3 +133,16 @@ The local Docker services use `restart: unless-stopped`, so containers should co
 *   **Database Migrations:** There is no ORM (like Prisma or Sequelize). Table schemas, indexes, and lightweight data repairs are managed via raw SQL statements inside `initDB()` in `backend/db.js` using `IF NOT EXISTS` and safe startup execution patterns.
 *   **API Security:** All backend modifications exposing or altering data MUST use the `verifyToken` middleware for frontend requests or `authenticateAPIKey` for external n8n webhooks.
 *   **Build Discipline:** After frontend/backend behavior changes, run `npm run lint`, `npm run build`, and relevant backend tests. The user prefers builds after changes to catch issues before deployment.
+
+## 9. Recent RFV Work
+Recent commits related to RFV/date behavior:
+*   `73033ca Aggregate RFM period buyers by prior tag` - backend RFV aggregation now groups period buyers by their prior tag.
+*   `ae73a54 Fix RFM period date display` - frontend date-only display and period recency fixed.
+*   `9a58b2a Improve RFM recency labels` - period recency labels show `Hoje`/`Ontem`/`X dias`.
+*   `f811d3c Rename visible RFM labels to RFV` - visible UI wording changed from RFM to RFV.
+
+Files most relevant to RFV:
+*   `backend/services/analyticsService.js` - `getRfmAnalytics`, date filters, RFV score/tag logic.
+*   `backend/test/analyticsService.test.js` - unit coverage for date filters and RFV aggregation.
+*   `src/pages/Rfm.tsx` - RFV page UI, matrix/table/export labels, period recency display.
+*   `src/components/DateRangePicker.tsx` and `src/dateRanges.ts` - local calendar date ranges and ISO query param formatting.