Add mash-schedule (Sud) automation: temp/rate sequencing + stirrer switching

brewpi.py had a dead -m/--model CLI arg and sude/*.json schedules were
pure data with no code to drive them, despite the README documenting
them as if they were already wired up.

Add components/sud.py's Sud, which loads a sude/*.json schedule and
steps through its Rasten (ramp -> hold -> optional wait-for-user ->
next rest), and tasks/sud.py's SudTask, which drives the temperature
controller's theta_soll/heatrate_soll from the current rest and
switches the stirrer between continuous (ramping) and intermittent
(holding, via stirrSpeedRast/stirrDutyRast/stirrCycleTime) operation.
Exposes progress on a new "Sud" WebSocket channel and accepts
Start/Confirm commands. Enabled via a new optional top-level "sud"
config key (see config.json.templ/.sim).

"Reached target" is detected via abs(theta_ist - theta_soll_set) <
tolerance rather than tc.state == HOLD, since the latter can still
read HOLD left over from the previous rest for one tick after a new
target is pushed (tc.state only updates on the controller's own,
independently-scheduled process() tick).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tasks/sud.py

@@ -0,0 +1,81 @@
+import asyncio
+from tasks import ATask
+from ws.message import MsgIo
+from utils.value import ChangedFloat
+from components import APid, AStirrer
+from components.sud import Sud, SudState
+
+# How close theta_ist needs to be to theta_soll_set to count as "reached".
+TEMP_REACHED_TOLERANCE = 0.2
+
+
+class SudTask(ATask):
+	def __init__(self, sud: Sud, tc: APid, stirrer: AStirrer, interval, msg_handler: MsgIo):
+		ATask.__init__(self, interval)
+		self.sud = sud
+		self.tc = tc
+		self.stirrer = stirrer
+		self.msg_handler = msg_handler
+		msg_handler.set_recv_handler(self.recv)
+
+	def on_rast_changed(self, rast):
+		if rast is not None:
+			self.tc.set_theta_soll(rast['temp'])
+			self.tc.set_heatrate_soll(rast['heatRate'])
+
+		asyncio.create_task(self.send({'Rast': {
+			'Index': self.sud.index,
+			'Temp': rast['temp'] if rast else None,
+			'HeatRate': rast['heatRate'] if rast else None,
+			'Time': rast['time'] if rast else None,
+			'WaitForUser': rast.get('waitForUser', False) if rast else None,
+		}}))
+
+	def on_state_changed(self, value):
+		asyncio.create_task(self.send({'State': str(value)}))
+
+		if value == SudState.RAMPING:
+			# Stir continuously while ramping to a new target temperature.
+			self.stirrer.set_duty_cycle(1.0)
+			self.stirrer.set_speed(self.sud.stirr_speed_heat)
+		elif value == SudState.HOLDING:
+			# Stir intermittently while holding at the rest's temperature.
+			self.stirrer.set_cycle_time(self.sud.stirr_cycle_time)
+			self.stirrer.set_duty_cycle(self.sud.stirr_duty_rast)
+			self.stirrer.set_speed(self.sud.stirr_speed_rast)
+		elif value in (SudState.WAIT_USER, SudState.DONE):
+			# Stop stirring while paused for the user or once the schedule is done.
+			self.stirrer.set_duty_cycle(1.0)
+			self.stirrer.set_speed(0)
+
+	def on_hold_remaining_changed(self, value):
+		asyncio.create_task(self.send({'HoldRemaining': value}))
+
+	async def recv(self, data):
+		for pair in data.items():
+			if 'Start' in pair[0]:
+				self.sud.start()
+			elif 'Confirm' in pair[0]:
+				self.sud.confirm()
+
+	async def send(self, data):
+		await self.msg_handler.send(data)
+
+	async def on_process(self):
+		print("{}: Started with interval {} s".format(self.msg_handler.get_key(), self.interval))
+
+		self.sud.set_on_changed('rast', self.on_rast_changed)
+		self.sud.set_on_changed('state', self.on_state_changed)
+		self.sud.set_on_changed('hold_remaining', ChangedFloat(self.on_hold_remaining_changed, prec=0).set)
+
+		asyncio.create_task(self.send({'Name': self.sud.name, 'Description': self.sud.description}))
+
+		while True:
+			if self.sud.state == SudState.RAMPING:
+				# Compare against the controller's own live setpoint/measurement
+				# rather than its state machine, which can still read HOLD from
+				# the previous rest for one tick after a new target is pushed.
+				if abs(self.tc.get_theta_ist() - self.tc.get_theta_soll_set()) < TEMP_REACHED_TOLERANCE:
+					self.sud.temp_reached()
+			self.sud.tick(self.interval)
+			await asyncio.sleep(self.interval)