/claim #7724

Summary

• Validates SSH key file content against database before SSH command execution
• Re-stores key file when content mismatch detected
• Invalidates stale multiplexed connections using outdated keys

Root Cause

The existing validateSshKey() only checked file existence, not content. When key files became stale or corrupted, SSH command would fail with a “Permission denied” error while multiplexed connections continued using outdated keys.

Changes

• SshMultiplexingHelper::validateSshKey() now uses Storage::disk(‘ssh-keys’) to compare file content with database value
• On mismatch: re-stores key and invalidates mux connections for all servers using that key
• Added 7 unit tests verifying implementation patterns

Issues

• fix #7724