Returns a link to download a PDF statement for the user's Bakkt bank account. Data comes from General Ledger (Blnk-style period_start/period_end when date_from/date_to are set; see Blnk statement guide). Supports flexible period via date_from and date_to (YYYY-MM-DD), max 366 days. Compliance: immutable snapshot once generated. Default: HTTP 501 until GL exposes GLGetAccountStatement. Set Lambda env GL_BAKKT_STATEMENT_ENABLED=true when GL is wired; then returns 200 with { url }. Omit dates for backend-defined default period when GL supports it. Merchant/API key with user_uuid in path.