* fix(doctor): read each client's own activation key
Doctor treated both `disabled: true` and `enabled: false` as a disabled
registration for every client except Grok. The installed clients each
read only one of them: Codex and Kimi Code honor `enabled` and still
load a server marked `disabled`, while Devin honors `disabled` and
still loads a server marked `enabled: false`. Doctor reported those
loaded registrations as stale, so `rea doctor --client codex` failed
with config_drift and setup offered to "repair" a working entry.
Skip the key each of these clients ignores. Other clients keep the
existing rule.
* fix(tests): resolve the Devin config root per platform in activation cases
The client activation cases wrote Devin's mcp_config.json under the
XDG root on every platform, but devinDirectory resolves APPDATA (or
~/AppData/Roaming) on Windows. Follow the client's per-platform root
so the cases exercise the file doctor actually reads there.