Impossible to deploy website if keychain target already contain other type of transaction than hosting

### Describe the problem you discovered

Problem description
It was impossible to deploy the website using the following command:

aeweb deploy --seed "PrivateAddressAeWalletInHexadecimalFormat" --endpoint https://testnet.archethic.net --path ./website --keychain-funding-service "archethic-wallet-fundingName" --keychain-website-service "archethic-wallet-WebSiteHostingName"
Steps to manage the problem
Via AeWallet: Create the keychains "fundingName" and "WebSiteHostingName".
Via AeWallet: Send UCO with messages to "fundingName" and "WebSiteHostingName".
Via AeWallet: send UCO with messages from "WebSiteHostingName" to "fundingName"
Via AeWallet: Retrieve the private address of the wallet in hexadecimal format via the dedicated menu (Menu/Security/SecretRecoveryPhrase => button View in Hexadecimal).
Run the command:
aeweb deploy --seed "PrivateAddressAeWalletInHexadecimalFormat" --endpoint https://testnet.archethic.net --path ./website --keychain-funding-service "archethic-wallet-fundingName" --keychain-website-service "archethic-wallet-WebSiteHostingName"
Error Output:

Connecting to https://testnet.archethic.net
Fetching keychain...
Keychain loaded with the funding/website services
Set(13) {
'http://185.34.143.63:4000',
'http://185.34.143.66:4000',
'http://188.166.236.224:4000',
'http://185.34.143.65:4000',
'http://185.34.143.68:4000',
'http://64.227.8.83:40000',
'http://185.34.143.64:4000',
'http://170.64.192.184:4000',
'http://185.34.143.67:4001',
'http://139.59.149.234:40000',
'http://164.92.66.71:4000',
'http://64.227.136.218:40000',
'https://testnet.archethic.net'
}
SyntaxError: Unexpected end of JSON input

### Describe the solution you'd like

_No response_

### Epic

_No response_

Start by reproducing the reported `aeweb deploy` command against the testnet with a keychain containing a non-hosting transaction, then trace the keychain-loading and deployment entry points that produce the JSON parse error. Done means deployment completes successfully when the keychain target already contains another transaction type.

Written by the indexing model from the issue text.