fix(cost): bill a session outside every workspace to its Linux account's user

A script's claude -p in a temp folder (the SG Flow eval runner strips the
pane's env) had no workspace, so its spend reached nobody's Today, the Users
page or a spend quota — ~$57 of a $74 day was missing from the status bar.

sessions.account records the Linux account a session ran as (the hook's
peer uid, else its folder for poller-made and old rows); a session no
workspace owns is owned by that account's user — a member's to them, the
host's to the admin ticked 'Owns this server's host account' (or the only
admin). Workspace ownership still wins.

server/routes/hooks.js

@@ -1643,6 +1643,8 @@ function ingestHook(body, pushSource = null, peer = { kind: "host" }) {
       } else {
         touchLaneFromHook(hook_type, data, tool, body.run_id, peer);
         bindRunSession(body.run_id, data.session_id, hook_type, data.source, tool);
+        // The Linux account it ran as: whose bill it is when no workspace owns it.
+        require("../lib/session-account").stampFromPeer(data.session_id, peer);
       }
     }
   } finally {