Grok hive hook fails on Windows: munder-hive.json command is not valid PowerShell #749

Version: Munder Difflin v0.5.5 (packaged, Windows 11), Grok CLI 1.0.52

What happens: every hook in ~/.grok/hooks/munder-hive.json exits 1 with a PowerShell ParserError: Unexpected token. Grok 1.0.52 runs hook commands in PowerShell (pwsh). The command is two quoted paths with nothing in front:
"…\hive-node.cmd" "…\grok-hook.cjs"
Grok ignores the failed hook, so tools still run. But Grok agents never reach the hive hook, so the hive gets no status, no session capture and no tracking.

Cause: installGrokHooks() builds the command with ["${launcher}", "${shim}"].join(" ") and rewrites the file on every Grok agent start, so a manual fix doesn't survive.

Fix: on win32, put PowerShell's call operator in front: & "…\hive-node.cmd" "…\grok-hook.cjs". Tested by hand: the hooks pass after /hooks → r.