Manual license periods and annual migration

v1.83.0

Features

• Manual commercial periods and agreed annual migration - existing customers
  can retrieve an agreed annual term through Update license status. A stable
  license identity allows a manually granted period before a Paddle subscription
  exists. After expiry, Subscribe annually opens checkout for the same holder
  and plan; completed payment links the subscription and enables paid renewal.
  Other perpetual licenses remain valid, and expiration never restricts features.