Add noctogram keycache to phosphor for chrome ip blinding usage

PiperOrigin-RevId: 552838601

quiche/blind_sign_auth/proto/get_initial_data.proto

diff --git a/quiche/blind_sign_auth/proto/get_initial_data.proto b/quiche/blind_sign_auth/proto/get_initial_data.proto
index bcbd834..fbd140c 100644
--- a/quiche/blind_sign_auth/proto/get_initial_data.proto
+++ b/quiche/blind_sign_auth/proto/get_initial_data.proto
@@ -61,4 +61,9 @@
   // General public metadata. Use metadata deserializer to inspect. Only set one
   // of this or public_metadata_info.
   bytes binary_public_metadata = 4 ;
+
+  message PrivacyPassData {
+    bytes token_key_id = 1;
+  }
+  PrivacyPassData privacy_pass_data = 5;
 }