Phase 1a: delete dead parallel app stack (~4,600 lines)

app.py was an abandoned skeleton (15 'pass # TODO' handlers, loads a
deleted .qss); everything else was reachable only from it:
ui_mainwindow.py (pyuic6 artifact), sc3-new.ui, motion_worker.py,
genesis_worker.py, coherent_hops_laser.py (stubs), scanning/ (dead C#
port + unused plan generator), config.json, plus helios_diagnostic.py
(sends wrong protocol commands) and helios_terminal.py (worse duplicate
of helios_test_app's Terminal tab).

hardware/__init__.py no longer wildcard-imports every driver, so the
stage driver imports without the uEye camera SDK installed.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

hardware/__init__.py

@@ -1,7 +1,6 @@
-"""Hardware driver modules for ScanEngine-3"""
-from .pybbd202 import ThorlabsServoDriver, TriggerBitsServo, AXIS_X, AXIS_Y, CONTROLLER
-from .t3r_driver import T3RDriver
-from .uc480_camera import *
-from .tektronix_base import *
-from .coherent_hops_laser import *
-from .genesis_core import *
+"""Hardware driver modules for ScanEngine-3.
+
+Import drivers by module (e.g. ``from hardware.t3r_driver import T3RDriver``);
+nothing is re-exported here so that importing one driver never drags in
+another driver's SDK (the uEye camera stack in particular).
+"""