Console: local instances get BT_AFFINITY=0xF0 (upper cores)

The game self-pins to core 0 by default; on the operator box core 0 is
shared with the console/relay/desktop, and the mission load drains
frame-paced -- a starved frame rate multiplied the operator's load time
to 3-5 min while internet testers loaded in ~20s (live finding, round
2).  The local-instance launcher now spreads the game across the upper
cores unless BT_AFFINITY is explicitly set.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tools/btoperator.py

@@ -807,6 +807,14 @@ class Operator(QMainWindow):
             # profile and the legacy arrow-drive bridge takes the keyboard
             # (user-reported: "launched with the wrong keymap again").
             env.insert("BT_PLATFORM", "glass")
+            # OPERATOR LOAD SPEED (2026-07-22, live finding): the game pins
+            # itself to CPU core 0 by default, which on the operator box is
+            # shared with the console/relay/desktop -- and the mission load
+            # drains frame-paced, so a starved frame rate multiplies load
+            # time (testers ~20s, operator 3-5 min).  Spread the local
+            # instance across the UPPER cores instead.
+            if "BT_AFFINITY" not in os.environ:
+                env.insert("BT_AFFINITY", "0xF0")
             if self.f_gauges.isChecked():
                 env.insert("BT_DEV_GAUGES", "1")
             if self.f_inside.isChecked():