Tighten pip shim write error

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Co-authored-by: bytemain <13938334+bytemain@users.noreply.github.com>

Author: Copilot

lib/util.lua

@@ -585,7 +585,7 @@ end
 local function writeWindowsFile(path, content)
     local file = io.open(path, "w")
     if not file then
-        error("Failed to write file: " .. path .. ". Check directory permissions and available disk space.")
+        error("Failed to write file: " .. path .. ". Check directory permissions and path validity.")
     end
     file:write(content)
     file:close()