Add ckUSDC canisters to snapshot (#351)

# Motivation

We want to add ckUSDC to NNS dapp and should have a way to test it.

# Changes

1. Add a logo file (copied from metadata of current mainnet
ckSepoliaUSDC).
2. Add a flag to `bin/dfx-token-deploy` to allow specifying a logo file.
3. Create ckUSDC canisters in `bin/dfx-stock-deploy`.
4. Add 10M ckUSDC to the faucet.

# Tested

Created a snapshot and used it in NNS dapp

bin/dfx-stock-deploy

@@ -59,12 +59,24 @@ dfx-token-deploy \
   --network "$DFX_NETWORK" \
   --yes
 
-: Mint 10M ckETH into the faucet address.
+: Set up ckUSDC canisters
+dfx-token-import --prefix ckusdc_ --commit "$DFX_IC_COMMIT"
+dfx-token-deploy \
+  --prefix ckusdc_ \
+  --token ckUSDC \
+  --decimals 6 \
+  --fee 4000 \
+  --logo-svg-file "$SOURCE_DIR/../ckUSDC-logo.svg" \
+  --network "$DFX_NETWORK" \
+  --yes
+
+: Mint 10M ckETH into the faucet addresses.
 # See https://github.com/dfinity/nns-dapp/blob/main/frontend/src/lib/api/dev.api.ts
 FAUCET_ADDRESS="jg6qm-uw64t-m6ppo-oluwn-ogr5j-dc5pm-lgy2p-eh6px-hebcd-5v73i-nqe"
 # The current identity was set as minting account and minting is done by
 # transferring from the minting account.
 dfx canister call cketh_ledger icrc1_transfer "(record {to=record{owner=principal \"$FAUCET_ADDRESS\"}; amount=10_000_000_000_000_000_000_000_000:nat})"
+dfx canister call ckusdc_ledger icrc1_transfer "(record {to=record{owner=principal \"$FAUCET_ADDRESS\"}; amount=10_000_000_000_000:nat})"
 
 : Add the nns root as a controller to the frontend canisters
 NNS_ROOT="$(dfx canister id nns-root --network "$DFX_NETWORK")"

bin/dfx-token-deploy

@@ -22,6 +22,7 @@ clap.define short=p long=prefix desc="Prefix for the local canister names" varia
 clap.define long=token desc="The token name/symbol" variable=TOKEN default="MyToken"
 clap.define long=decimals desc="Number of decimals to use in ledger canister" variable=DECIMALS default="8"
 clap.define long=fee desc="The transaction fee to set" variable=FEE default="10"
+clap.define long=logo-svg-file desc="SVG file to use as token logo" variable=LOGO_SVG_FILE default=""
 clap.define short=y long=yes desc="Deploy even if there are existing canisters." variable=DFX_YES nargs=0
 clap.define short=c long=check desc="Check that the canisters are present and correct." variable=DFX_CHECK nargs=0
 clap.define short=m long=mode desc="Canister install mode." variable=DFX_MODE default="reinstall"
@@ -47,6 +48,12 @@ deploy_token() {
 
   echo "Step 1: deploying ledger canister..."
   DFX_IDENTITY_PRINCIPAL="$(dfx identity get-principal)"
+  if [[ -n "${LOGO_SVG_FILE:-}" ]]; then
+    LOGO_BASE64="$(base64 -i "$LOGO_SVG_FILE")"
+    TOKEN_METADATA="vec { record { \"icrc1:logo\"; variant { Text = \"data:image/svg+xml;base64,${LOGO_BASE64}\" }; } }"
+  else
+    TOKEN_METADATA="vec {}"
+  fi
   dfx deploy "${LOCAL_PREFIX}ledger" --network "$DFX_NETWORK" --argument "(variant {
   Init = record {
      token_symbol = \"$TOKEN\";
@@ -55,7 +62,7 @@ deploy_token() {
      transfer_fee = $FEE;
      max_memo_length = opt 64;
      decimals = opt $DECIMALS;
-     metadata = vec {};
+     metadata = $TOKEN_METADATA;
      initial_balances = vec { record { record { owner = principal \"$DFX_IDENTITY_PRINCIPAL\"; }; 10_000_000; }; };
      archive_options = record {
          num_blocks_to_archive = 10_000;