feat!: deprecate issuer field

Author: Gozala

packages/upload-api/src/types.ts

@@ -515,7 +515,12 @@ export interface StoreAddInput {
   link: UnknownLink
   size: number
   origin?: UnknownLink
-  issuer: DID
+
+  /**
+   * @deprecated - Issuer of the invocation is irrelevant as long as
+   * they have authorization to invoke on subject `space`.
+   */
+  issuer?: DID
   invocation: UCANLink
 }