SSH key auth passes test, but script install fails with "Load key ... error in libcrypto" (rsync/ssh)

[emerick-biron]

✅ Have you read and understood the above guidelines?

yes

📝 Provide a clear and concise description of the issue.

Using PVE-Scripts-Local with SSH key only authentication to a Proxmox VE host:

• The Saved Servers "Test Connection" reports success (SSH key authentication successful).
• But installing any script fails. The runtime shows "Load key ... error in libcrypto" during rsync/ssh, then "Permission denied (publickey,password)".

My Proxmox VE host authorized_keys contains key entry:
ssh-... <public_key_here>
I have tested with both ED25519 and RSA keys. Same result.

🔄 Steps to reproduce the issue.

1. On the Proxmox VE host (192.168.1.40), add an authorized_keys entry for root:
   ssh-ed25519 AAAA... or ssh-rsa AAAA...
2. In PVE-Scripts-Local:
   • Authentication Type: SSH key only
   • Host: 192.168.1.40
   • No password set
3. In Saved Servers, click "Test Connection".
   Result: "Connection Successful" and "SSH key authentication successful - credentials verified".
4. Try to install a script, for example: scripts/ct/librespeed-rust.sh.

❌ Paste the full error output (if available).

[22:21:19] [START] Starting SSH execution of scripts/ct/librespeed-rust.sh on pve (192.168.1.40)
[22:21:19] [ERROR] Warning: Permanently added '192.168.1.40' (ED25519) to the list of known hosts.

[22:21:19] [ERROR] Load key "/tmp/ssh-key-BPj76e/private_key": error in libcrypto

[22:21:19] [ERROR] Permission denied, please try again.
[22:21:19] [ERROR] Permission denied, please try again.
[22:21:19] [ERROR] root@192.168.1.40: Permission denied (publickey,password).

[22:21:19] [ERROR] rsync: connection unexpectedly closed (0 bytes received so far) [sender]
[22:21:19] [ERROR] rsync error: unexplained error (code 255) at io.c(232) [sender=3.4.1]

[22:21:19] [ERROR] SSH execution failed: rsync failed with code 255
[22:21:19] [ERROR] Failed to start SSH execution: rsync failed with code 255

🖼️ Additional context (optional).

No response