On Windows, a black console (conhost) window flashed briefly when CodeGraph ran as a background MCP server. Several child spawns were missing `windowsHide: true`, so Windows created a visible console for the child: - scripts/npm-shim.js — launching the bundled runtime (every server start / daemon-idle reconnect) and the self-heal `tar` extraction of a missing platform bundle. - src/reasoning/login.ts — the detached `cmd /c start` browser open. - src/upgrade/index.ts — package-manager spawn (console-attached, so no flash in practice, but set for uniformity: every child spawn now hides). The daemon spawn (#411) and all git execFileSync sites already set it; this closes the remaining gaps. Adds an all-platforms source guard to __tests__/npm-shim.test.ts asserting every spawn in the shim sets windowsHide. Closes #1092 Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>