docs: update Ywallet demo section for phase 2 (#652)

* docs: update Ywallet demo section for phase 2

* fix unrelated SecretPackage -> KeyPackage

* Update book/src/zcash/ywallet-demo.md

book/src/tutorial/trusted-dealer.md

@@ -59,7 +59,7 @@ to generate signatures.
 ```
 
 ```admonish danger
-The `SecretPackage` contents must be stored securely. For example:
+The `KeyPackage` contents must be stored securely. For example:
 
 - Make sure other users in the system can't read it;
 - If possible, use the OS secure storage such that the package

book/src/zcash/ywallet-demo.md

@@ -161,71 +161,60 @@ When prompted, paste the UFVK generated previously.
 The program will print a SIGHASH and a Randomizer.
 
 Now you will need to simulate two participants and a Coordinator to sign the
-transaction. It's probably easier to open three terminals.
+transaction, and the FROST server that handles communications between them.
+It's probably easier to open four terminals.
 
-In the first one, the Coordinator, run (in the same folder where key
-generation was run):
+In the first one, the server, run (in the same folder where key generation was
+run):
 
 ```
-cargo run --bin coordinator --features redpallas -- --cli
+RUST_LOG=debug cargo run --bin server --features redpallas --
+```
+
+In the second one, the Coordinator, run (in the same folder where key generation
+was run):
+
+```
+cargo run --bin coordinator --features redpallas -- --http -r -
 ```
 
 And then:
 
 - It should read the public key package from `public-key-package.json`.
 - Type `2` for the number of participants.
-- Paste the identifier of the first participant, you can see it in
-  `key-package-1.json`. If you used trusted dealer key generation, it will be
-  `0100000000000000000000000000000000000000000000000000000000000000`.
+- Copy the session ID that is printed.
 
 
-Create a new terminal, for participant 1, and run:
+In the third terminal, Participant 1, run the following, replacing
+`<SESSION_ID>` with the session ID you have just copied:
 
 ```
-cargo run --bin participant --features redpallas -- --cli --key-package key-package-1.json
+cargo run --bin participant --features redpallas -- --cli --key-package key-package-1.json -s <SESSION_ID>
 ```
 
-And then:
-
-- Copy the SigningCommitments line and paste into the Coordinator CLI.
-
-Go back to the coordinator and:
-
-- Paste the second identifier, e.g.
-  `0200000000000000000000000000000000000000000000000000000000000000`.
-
-Create a new terminal, for participant 2, and run:
+In the fourth terminal, for Participant 2, run the following, again replacing
+the session ID:
 
 ```
-cargo run --bin participant --features redpallas -- --cli --key-package key-package-2.json
+cargo run --bin participant --features redpallas -- --cli --key-package key-package-2.json -s <SESSION_ID>
 ```
 
-And then:
+Go back to the Coordinator CLI:
 
-- Copy the SigningCommitments line and paste into the Coordinator CLI.
 - When prompted for the message to be signed, paste the SIGHASH printed by the
   signer above (just the hex value, e.g.
   ``4d065453cfa4cfb4f98dbc9cff60c4a3904ed91c523b8ef8d67d28bea7f12ea3``).
-
-You should be at the Coordinator CLI. Paste the Randomizer generated by the
-signer before and copy the Signing Package line that it was printed by the
-Coordinator CLI before the Randomizer prompt.
+- When prompted for the randomizer, paste the randomizer printed by the signer
+  above (again just the hex value)
 
 ```admonish warning
 If you prefer to pass the randomizer as a file by using the `--randomizer`
 argument, you will need to convert it to binary format.
 ```
 
-Switch to participant 1 and:
-
-- Paste the Signing Package
-- Paste the Randomizer printed by the signer before.
-- Copy the SignatureShare line and paste it into the Coordinator CLI.
-
-Do the same for participant 2.
-
-You should be at the Coordinator CLI. It has just printed the final
-FROST-generated signature. Hurrah! Copy it (just the hex value).
+The protocol should run and complete succesfully. You should still be at the
+Coordinator CLI. It has just printed the final FROST-generated signature.
+Hurrah! Copy it (just the hex value).
 
 Go back to the signer and paste the signature. It will write the raw signed
 transaction to the file you specified.