Add largeBlob support per w3c/webauthn#1470

In the spec: https://w3c.github.io/webauthn/#sctn-large-blob-extension

Author: lgarron

src/extended/json.ts

@@ -20,6 +20,7 @@ interface ExtendedExtensionsClientInputsJSON {
     second?: Base64urlString;
   };
   largeBlob?: {
+    support?: "required" | "preferred";
     read?: boolean;
     write?: Base64urlString;
   };
@@ -33,6 +34,7 @@ interface ExtendedAuthenticationExtensionsClientOutputsJSON {
     credProps: boolean;
   };
   largeBlob?: {
+    supported?: boolean;
     blob?: Base64urlString;
     written?: boolean;
   };

src/extended/schema.ts

@@ -22,6 +22,7 @@ const authenticationExtensionsClientInputsSchema: Schema = {
     credProps: optional(copyValue),
   }),
   largeBlob: optional({
+    support: optional(copyValue),
     read: optional(copyValue),
     write: optional(convertValue),
   }),
@@ -33,6 +34,7 @@ const authenticationExtensionsClientOutputsSchema: Schema = {
   uvm: optional(copyValue),
   credProps: optional(copyValue),
   largeBlob: optional({
+    supported: optional(copyValue),
     blob: optional(convertValue),
     written: optional(copyValue),
   }),