- shell-env: detect Git Bash via MSYSTEM env var when SHELL is unset (#3366)
On some Git Bash installations SHELL is not set but MSYSTEM (MINGW64/MSYS)
is always present. Check MSYSTEM before PSModulePath to avoid emitting
PowerShell syntax in bash shells.
- session-state: resolve legacy agent names in resolveRegisteredAgentName (#3272)
Historical sessions stored agent names like 'Sisyphus (Ultraworker)' which
don't match the current registered format. Fall back to getAgentConfigKey
for legacy/parenthesized name resolution before returning the raw name.
- config-migration: skip backup when file content is unchanged (#3222)
Compare serialized config with existing file content before creating a
timestamped .bak file. Only create backup when the on-disk content
actually differs from the migrated content.
On Windows, PSModulePath is always set by the system even when the
active shell is Git Bash (via SHELL env var). This caused the
non-interactive-env hook to generate PowerShell syntax ($env:VAR=val)
for bash shells, resulting in 15+ errors per command.
The fix prioritizes SHELL over PSModulePath since an explicit SHELL
variable indicates the user's chosen shell, while PSModulePath is just
a system-wide module path that doesn't indicate the active shell.
Fixes: #3338
YeonGyu-Kim