Product tenant statistics by month

`current` — this month computed live (same calculator as the monthly snapshot); `months` — stored snapshots, newest first, at most 24. Month object: {year, month, tenantCount, actualTenantCount, tiers{included,lite,max,custom}, priceUsd, ownKeys, aiTokensUsed, aiTokensLimit, aiCostUsd}.

curl -X GET "https://example.com/api/v2/products/497f6eca-6276-4993-bfeb-53cbbbba6f08/stats"

{}

{  "message": {    "error": "Your request was made with invalid credentials."  }}

{  "message": {    "error": "You are not allowed to perform this action."  }}

{  "message": {    "error": "Page not found"  }}