Retail sales dashboard with filters, table, and chart

Build a static web dashboard for a small retail team to explore sales from a CSV export. The user uploads (or picks the bundled sample) a CSV with columns date, product, region, revenue. The page shows: filters by product and region and a date range; a table of monthly revenue totals for the filtered rows; and a bar chart of revenue by region for the filtered rows, which updates when filters change. Include a realistic sample CSV (at least 60 rows across 4 regions, 5 products and 6 months) so the dashboard is useful with no upload. Invalid rows (missing columns, non-numeric revenue, bad dates) are skipped and the page says how many were skipped. It must run by opening it locally or serving the folder statically, with no build step and no network access. Include a short README explaining how to run it and the CSV format.