Vendor Central weekly digest

Read https://www.sellermate.ai/api-docs first. It documents the SellerMate Public API: REST over HTTPS, X-API-Key auth, and every tool with its parameters is on that page. Every tool is POST https://api.sellermate.ai/public/v1/tools/{name} with a JSON body.

Build me a weekly Vendor Central digest for one vendor account.

Every Monday:
- Pull last week's sales per ASIN with get_vendor_sales_performance: ordered units and revenue, shipped units and revenue, glance views, customer returns
- Pull current vendor inventory with get_vendor_inventory
- Flag ASINs where shipped revenue is more than [15]% below ordered revenue, and ASINs with under [3] weeks of cover at last week's shipped rate
- Send one HTML email with totals, the two flag lists and the top 10 ASINs by ordered revenue

Resolve the account with get_user_context and confirm its accountType is vendor.

Rules:
- My key is in the SELLERMATE_API_KEY environment variable. Send it as the X-API-Key header. Never hard-code it or log it.
- Call get_user_context first and use the accounts it returns. Don't invent account ids.
- Report tools are paginated (page, page_size up to 500, pagination.hasMore). Walk every page.
- On a 429, wait for the Retry-After header and retry. On a 401 or 403, stop and tell me.
- Show me the plan and the code before running anything that writes.

Stack: Python 3 with requests, email via SMTP settings in environment variables.