Adapt Sud/SudTask/demo to the new flat heat/hold schedule schema

sude/sud_0010.json moved from a list of combined ramp+hold+wait
"Rasten" with global stirrer constants to a flat "schedule" list of
explicit {"type": "heat"|"hold", ...} steps, each carrying its own
stirrer_speed/stirrer_time_on/stirrer_time_off and an optional
user_wait_for_continue (+ user_message).

- components/sud.py: Sud now tracks the current `step` instead of
  `rast`; "heat" steps enter RAMPING (advanced externally via
  temp_reached()), "hold" steps enter HOLDING and count down
  `duration` minutes (0 if omitted). Either step type can pause in
  WAIT_USER via user_wait_for_continue, surfaced through the new
  user_message attribute.
- tasks/sud.py: SudTask only pushes theta_soll/heatrate_soll on
  "heat" steps, converts each step's stirrer_time_on/off into a
  duty_cycle/cycle_time on every step change (replacing the old
  state-based RAMPING/HOLDING stirrer switching), and broadcasts
  user_message changes. Stirring is now fully schedule-driven instead
  of implicitly stopped on WAIT_USER/DONE (DONE still stops it, since
  there's no step left to read settings from).
- scripts/demos/sud/demo_sud.py: mirrors the same step-driven wiring.
- README's Mash schedules section rewritten for the new schema.

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

sude/sud_0010.json

@@ -5,35 +5,83 @@
 	"pot_material"		: "Edelstahl 18/10",
 	"Schuettung_kg"		: 5.21,
 	"Wasser_kg"			: 22,
-	"stirrSpeedHeat"	: 30,
-	"stirrSpeedRast"	: 30,
-	"stirrDutyRast"		: 1.0,
-	"stirrCycleTime"	: 120,
-	"Rasten" :
+	"schedule":
 	[
 		{
-			"time"			:  0,
-			"temp"			:  57.0,
-			"heatRate"		:  1.00,
-			"waitForUser"	: true
+			"type": "heat",
+			"descr": "Heizen für Einmaischen",
+			"rate": 1.8,
+			"temp": 57,
+			"stirrer_speed": 50,
+			"stirrer_time_on": 90,
+			"stirrer_time_off": 0
 		},
 		{
-			"time"			:  40,
-			"temp"			:  63.0,
-			"heatRate"		:  1.00,
-			"waitForUser"	: false
+			"type": "hold",
+			"descr": "Einmaischen einfüllen",
+			"stirrer_speed": 0,
+			"user_message": "Bitte Malz einfüllen und bestätigen",
+			"user_wait_for_continue"	: true
 		},
 		{
-			"time"			:  30,
-			"temp"			:  72.0,
-			"heatRate"		:  1.00,
-			"waitForUser"	: true
+			"type": "hold",
+			"descr": "Einmaischen Rast",
+			"duration"	:  30,
+			"stirrer_speed": 30,
+			"stirrer_time_on": 30,
+			"stirrer_time_off": 30
 		},
 		{
-			"time"			:  0,
-			"temp"			:  76.0,
-			"heatRate"		:  1.00,
-			"waitForUser"	: true
+			"type": "heat",
+			"descr": "Heizen Glucose-Rast",
+			"rate": 1.0,
+			"temp": 63,
+			"stirrer_speed": 50,
+			"stirrer_time_on": 90,
+			"stirrer_time_off": 0
+		},
+		{
+			"type": "hold",
+			"descr": "Halten Glucose-Rast",
+			"duration"	:  40,
+			"stirrer_speed": 30,
+			"stirrer_time_on": 30,
+			"stirrer_time_off": 30
+		},
+		{
+			"type": "heat",
+			"descr": "Heizen Verzuckerungs-Rast",
+			"rate": 1.0,
+			"temp": 72,
+			"stirrer_speed": 50,
+			"stirrer_time_on": 90,
+			"stirrer_time_off": 0
+		},
+		{
+			"type": "hold",
+			"descr": "Halten Verzuckerungs-Rast",
+			"duration"	:  30,
+			"stirrer_speed": 30,
+			"stirrer_time_on": 30,
+			"stirrer_time_off": 30
+		},
+		{
+			"type": "heat",
+			"descr": "Heizen Abmaischen",
+			"rate": 1.0,
+			"temp": 76,
+			"stirrer_speed": 50,
+			"stirrer_time_on": 90,
+			"stirrer_time_off": 0
+		},
+		{
+			"type": "hold",
+			"descr": "Halten Abmaischen",
+			"duration"	:  30,
+			"stirrer_speed": 30,
+			"stirrer_time_on": 30,
+			"stirrer_time_off": 30,
+			"user_wait_for_continue"	: true
 		}
 	]
 }