feat(print-options): add "Auto" state to bed levelling, flow & nozzle-offset calibration

Bed levelling, flow calibration, and nozzle-offset calibration were on/off
only, so the sole way to run bed levelling was to force a full level before
every print. Bambu Studio has always offered a third "Auto" state that lets
the printer skip the calibration when it was done recently -- the state most
users actually want. Make these three options tri-state (off/on/auto),
defaulting to auto, and leave vibration/layer-inspect/timelapse as on/off
(Bambu Studio exposes no auto for those).

Wire encoding follows Bambu Studio's source exactly: each option sends a JSON
bool (true only for "on") plus a companion int -- off=0, on=1, auto=2. The
bool fields stay booleans (the #1478 H2S regression); only the companion int
widened from {0,1} to {0,1,2}. #1721's observation that stage 8/39 stays
queued when sending 2 is the auto contract (queued, skipped at runtime if
recent), not a broken "off".

- schemas: TriState = Literal[off/on/auto] with a BeforeValidator coercing
  legacy bool / 0-1 / true-false so old clients and un-migrated rows validate
- model + migration: boolean columns -> String; SQLite via column affinity +
  data backfill, PostgreSQL via ALTER COLUMN TYPE guarded on information_schema
  (verified on both dialects); settings rows normalised true/false -> on/off
- MQTT: start_print takes the tri-state strings and emits the paired bool+int
- Virtual Printer: reconstructs the slicer's auto/on/off from the int companion
  (auto_bed_leveling / extrude_cali_flag) in both capture paths
- frontend: CalibrationMode type; off/auto/on segmented controls in the print
  dialog, queue bulk-edit, and Settings -> Workflow; calibrationMode_* strings
  in all 11 locales

frontend/src/components/PrintModal/PrintOptions.tsx

@@ -1,15 +1,30 @@
 import { useState } from 'react';
 import { Settings, ChevronDown, ChevronUp, Flame } from 'lucide-react';
 import { useTranslation } from 'react-i18next';
-import type { PrintOptionsProps, PrintOptions as PrintOptionsType, PreheatOverride } from './types';
+import type {
+  PrintOptionsProps,
+  PrintOptions as PrintOptionsType,
+  PreheatOverride,
+  CalibrationMode,
+} from './types';
+import {
+  CALIBRATION_MODES,
+  CALIBRATION_MODE_ACTIVE,
+  CALIBRATION_MODE_INACTIVE,
+} from '../../utils/calibrationMode';
 
 type OptionConfig = {
   key: keyof PrintOptionsType;
   label: string;
   desc: string;
   dualNozzleOnly?: boolean;
+  /** Tri-state (off/on/auto) rather than a plain on/off pair. */
+  tristate?: boolean;
 };
 
+// On/off options render as the same button pair, minus the "auto" choice.
+const BOOLEAN_MODES = ['off', 'on'] as const;
+
 /**
  * Print options toggle panel with collapsible UI.
  * Shows bed levelling, flow/vibration calibration, layer inspection, timelapse,
@@ -27,18 +42,22 @@ export function PrintOptionsPanel({
   // Labels/descriptions reuse the settings.default* namespace — identical strings,
   // already translated across all locales. Only nozzle_offset_cali is new (#1682).
   const printOptionsConfig: OptionConfig[] = [
-    { key: 'bed_levelling', label: t('settings.defaultBedLevelling'), desc: t('settings.defaultBedLevellingDesc') },
-    { key: 'flow_cali', label: t('settings.defaultFlowCali'), desc: t('settings.defaultFlowCaliDesc') },
+    { key: 'bed_levelling', label: t('settings.defaultBedLevelling'), desc: t('settings.defaultBedLevellingDesc'), tristate: true },
+    { key: 'flow_cali', label: t('settings.defaultFlowCali'), desc: t('settings.defaultFlowCaliDesc'), tristate: true },
     { key: 'vibration_cali', label: t('settings.defaultVibrationCali'), desc: t('settings.defaultVibrationCaliDesc') },
     { key: 'layer_inspect', label: t('settings.defaultLayerInspect'), desc: t('settings.defaultLayerInspectDesc') },
     { key: 'timelapse', label: t('settings.defaultTimelapse'), desc: t('settings.defaultTimelapseDesc') },
-    { key: 'nozzle_offset_cali', label: t('settings.defaultNozzleOffsetCali'), desc: t('settings.defaultNozzleOffsetCaliDesc'), dualNozzleOnly: true },
+    { key: 'nozzle_offset_cali', label: t('settings.defaultNozzleOffsetCali'), desc: t('settings.defaultNozzleOffsetCaliDesc'), dualNozzleOnly: true, tristate: true },
   ];
 
   const visibleOptions = printOptionsConfig.filter(o => !o.dualNozzleOnly || showDualNozzleOptions);
 
-  const handleToggle = (key: keyof PrintOptionsType) => {
-    onChange({ ...options, [key]: !options[key] });
+  const handleToggle = (key: keyof PrintOptionsType, value: boolean) => {
+    onChange({ ...options, [key]: value });
+  };
+
+  const handleCalibrationMode = (key: keyof PrintOptionsType, mode: CalibrationMode) => {
+    onChange({ ...options, [key]: mode });
   };
 
   const handlePreheatOverride = (next: PreheatOverride) => {
@@ -81,26 +100,56 @@ export function PrintOptionsPanel({
       </button>
       {isExpanded && (
         <div className="mt-2 bg-bambu-dark rounded-lg p-3 space-y-2">
-          {visibleOptions.map(({ key, label, desc }) => (
-            <label key={key} className="flex items-center justify-between cursor-pointer group">
-              <div>
-                <span className="text-sm text-white">{label}</span>
-                <p className="text-xs text-bambu-gray">{desc}</p>
+          {visibleOptions.map(({ key, label, desc, tristate }) =>
+            tristate ? (
+              <div key={key} className="flex items-center justify-between gap-3">
+                <div>
+                  <span className="text-sm text-white">{label}</span>
+                  <p className="text-xs text-bambu-gray">{desc}</p>
+                </div>
+                <div className="flex gap-1 shrink-0">
+                  {CALIBRATION_MODES.map((mode) => (
+                    <button
+                      key={mode}
+                      type="button"
+                      onClick={() => handleCalibrationMode(key, mode)}
+                      className={`px-2.5 py-1 text-xs rounded transition-colors ${
+                        options[key as 'bed_levelling'] === mode
+                          ? CALIBRATION_MODE_ACTIVE[mode]
+                          : CALIBRATION_MODE_INACTIVE
+                      }`}
+                    >
+                      {t(`settings.calibrationMode_${mode}`)}
+                    </button>
+                  ))}
+                </div>
               </div>
-              <div
-                className={`relative w-10 h-5 rounded-full transition-colors ${
-                  options[key as 'bed_levelling'] ? 'bg-bambu-green' : 'bg-bambu-dark-tertiary'
-                }`}
-                onClick={() => handleToggle(key)}
-              >
-                <div
-                  className={`absolute top-0.5 w-4 h-4 rounded-full bg-white transition-transform ${
-                    options[key as 'bed_levelling'] ? 'translate-x-5' : 'translate-x-0.5'
-                  }`}
-                />
+            ) : (
+              <div key={key} className="flex items-center justify-between gap-3">
+                <div>
+                  <span className="text-sm text-white">{label}</span>
+                  <p className="text-xs text-bambu-gray">{desc}</p>
+                </div>
+                <div className="flex gap-1 shrink-0">
+                  {BOOLEAN_MODES.map((mode) => {
+                    const active = (options[key as 'vibration_cali'] ? 'on' : 'off') === mode;
+                    return (
+                      <button
+                        key={mode}
+                        type="button"
+                        onClick={() => handleToggle(key, mode === 'on')}
+                        className={`px-2.5 py-1 text-xs rounded transition-colors ${
+                          active ? CALIBRATION_MODE_ACTIVE[mode] : CALIBRATION_MODE_INACTIVE
+                        }`}
+                      >
+                        {t(`settings.calibrationMode_${mode}`)}
+                      </button>
+                    );
+                  })}
+                </div>
               </div>
-            </label>
-          ))}
+            ),
+          )}
 
           {/* Preheat / heat-soak per-item override (#1468). Defaults to
               'inherit' which means the global Settings → Workflow toggle

frontend/src/components/PrintModal/types.ts

@@ -1,4 +1,6 @@
-import type { PrintQueueItem, Printer } from '../../api/client';
+import type { PrintQueueItem, Printer, CalibrationMode } from '../../api/client';
+
+export type { CalibrationMode };
 
 /**
  * Mode of operation for the PrintModal.
@@ -44,12 +46,12 @@ export interface PrintModalProps {
 export type PreheatOverride = 'inherit' | 'on' | 'off';
 
 export interface PrintOptions {
-  bed_levelling: boolean;
-  flow_cali: boolean;
+  bed_levelling: CalibrationMode;
+  flow_cali: CalibrationMode;
   vibration_cali: boolean;
   layer_inspect: boolean;
   timelapse: boolean;
-  nozzle_offset_cali: boolean;
+  nozzle_offset_cali: CalibrationMode;
   // Per-item preheat / heat-soak override (#1468). 'inherit' uses the global
   // Settings → Workflow toggle; 'on' / 'off' force the per-print decision.
   // chamber_target_override is non-null to bypass the per-filament-type
@@ -62,12 +64,12 @@ export interface PrintOptions {
  * Default print options values.
  */
 export const DEFAULT_PRINT_OPTIONS: PrintOptions = {
-  bed_levelling: true,
-  flow_cali: false,
+  bed_levelling: 'auto',
+  flow_cali: 'auto',
   vibration_cali: true,
   layer_inspect: false,
   timelapse: false,
-  nozzle_offset_cali: true,
+  nozzle_offset_cali: 'auto',
   preheat_override: 'inherit',
   preheat_chamber_target_override: null,
 };