csh Shell Incompatibility Bug Fixed Across SSH Codebase With Unified Helper

A user reported that WordPress auto-detect via SSH always failed while the WP-CLI path test on the same connection succeeded, pointing to an asymmetric bug. Investigation revealed the root cause was csh, the default login shell on some hosts like Sakura Internet, which cannot interpret Bash/POSIX idioms such as 2>/dev/null passed through Python's paramiko SSH library. An earlier fix had wrapped commands in /bin/sh -c for one endpoint only, leaving all other SSH-command APIs still broken on csh hosts. Developers resolved this by introducing a _safe_run helper function that automatically wraps every SSH command in /bin/sh -c, ensuring POSIX shell interpretation regardless of the user's login shell. A static analysis test was also added to the codebase to prevent raw SSH command calls from being introduced again in the future.