fix(kprofiles): read the nozzle diameter the printer actually sent (issue #1748)

Every K-profile came back as 0.4mm on printers running any other
nozzle (#1748, reporters @Liquidmasl and @jmoore-skild). The printer
puts nozzle_diameter on the extrusion_cali_get envelope only; the
per-filament entries carry setting_id, filament_id, name, k_value,
n_coef and cali_idx, and nothing else. The parser read the field per
entry with a hardcoded "0.4" fallback, so the fallback fired on every
profile of every response. The envelope value was already in scope,
read into response_nozzle and used only to match the request.

This never reproduced on H2D because that firmware does include the
field per entry. Both construction sites are in the same handler, so
the code path is shared; what differs is the payload, and every
single-nozzle model omits it.

The display was the least of it. Editing is delete-and-re-add on
single-nozzle printers, and the dialog rebuilt nozzle_id and
nozzle_diameter from its own greyed-out selects, so saving an
untouched 0.6mm profile rewrote it on the printer as HH00-0.4.
Deleting aimed extrusion_cali_del at the wrong nozzle the same way.
Both now pass through what the printer reported. The cali_idx cascade
in inventory.py, spoolman_inventory.py and spoolman.py matches on
nozzle_diameter, so on a 0.6 or 0.8 nozzle it never found the
printer-side entry and the assignment silently failed to stick --
that is the "cannot auto-map a K-profile" half of the report, fixed
at the source without touching those three call sites.

nozzle_id has no source in the payload at all, and state.nozzles
carries material (hardened_steel), not flow, so it cannot honestly
produce HH/HS. Rather than keep inventing one, the UI now says the
printer did not report it: the card shows the diameter alone, the
dialog shows "Not reported by printer", and the High Flow / Standard
filter is hidden instead of being offered as a control that can only
ever empty the list. Import stops stamping HH00 on profiles whose
source reported none.

Also correlates K-profile requests by sequence_id. Responses were
matched by nozzle diameter through a single shared expectation slot,
so a second request overwrote the first's and the first's valid
answer was discarded as a mismatch -- the "Failed to get K-profiles
after 3 attempts" in the same logs, with the printer having answered
correctly both times. Pending state is now one entry per request,
keyed by the id we already send, with the nozzle match kept as a
fallback for firmware that does not echo it back.

Fixes the flow-type select naming a new profile with the opposite
label, which contradicted the identical expression 44 lines above it.

frontend/src/components/KProfilesView.tsx

@@ -42,16 +42,21 @@ const truncateK = (value: string) => {
   return (Math.trunc(num * 1000) / 1000).toFixed(3);
 };
 
-// Get flow type label from nozzle_id (e.g., "HH00-0.4" -> "HF", "HS00-0.4" -> "S")
+// Get flow type label from nozzle_id (e.g., "HH00-0.4" -> "HF", "HS00-0.4" -> "S").
+// Single-nozzle printers omit nozzle_id from their extrusion_cali_get response
+// entirely (#1748), and there is no other field to recover the flow type from —
+// so return '' and let the caller show nothing rather than assert "Standard".
 const getFlowTypeLabel = (nozzleId: string) => {
   if (nozzleId.startsWith('HH')) return 'HF';  // High Flow
-  return 'S';  // Standard Flow (default)
+  if (nozzleId.startsWith('HS')) return 'S';   // Standard Flow
+  return '';  // not reported by the printer
 };
 
-// Extract nozzle type prefix from nozzle_id (e.g., "HH00-0.4" -> "HH00")
+// Extract nozzle type prefix from nozzle_id (e.g., "HH00-0.4" -> "HH00").
+// '' when the printer reported no nozzle_id — see getFlowTypeLabel.
 const getNozzleTypePrefix = (nozzleId: string) => {
   const match = nozzleId.match(/^([A-Z]{2}\d{2})/);
-  return match ? match[1] : 'HH00';
+  return match ? match[1] : '';
 };
 
 // Extract filament name from profile name (e.g., "High Flow_Devil Design PLA Basic" -> "Devil Design PLA Basic")
@@ -120,7 +125,7 @@ function KProfileCard({ profile, onEdit, onCopy, selectionMode, isSelected, onTo
             </span>
           )}
           <span className="text-xs text-bambu-gray whitespace-nowrap">
-            {flowType} {diameter}
+            {[flowType, diameter].filter(Boolean).join(' ')}
           </span>
         </div>
         {note && (
@@ -183,8 +188,12 @@ function KProfileModal({
   );
   const [filamentId, setFilamentId] = useState(profile?.filament_id || '');
   // Split nozzle into type and diameter
+  // Both selects are read-only while editing: they report what the printer
+  // holds, they don't set it. '' means the printer reported no nozzle_id, which
+  // single-nozzle models never do (#1748) — showing "High Flow" there was the
+  // UI inventing a value the printer never sent.
   const [nozzleType, setNozzleType] = useState(
-    profile?.nozzle_id ? getNozzleTypePrefix(profile.nozzle_id) : 'HH00'
+    profile ? getNozzleTypePrefix(profile.nozzle_id) : 'HH00'
   );
   const [modalDiameter, setModalDiameter] = useState(
     profile?.nozzle_diameter || nozzleDiameter
@@ -316,14 +325,22 @@ function KProfileModal({
     // Combine nozzle type and diameter into nozzle_id (e.g., "HH00-0.4")
     const nozzleId = `${nozzleType}-${modalDiameter}`;
 
+    // An edit is delete + re-add on single-nozzle printers, so the nozzle
+    // fields have to survive the round trip untouched — both selects are
+    // disabled while editing. Rebuilding them from the selects is what let a
+    // 0.6mm profile come back as "HH00-0.4" once the parse defaults had
+    // stamped it 0.4 (#1748); pass through what the printer reported instead.
+    const editNozzleId = profile ? profile.nozzle_id : nozzleId;
+    const editDiameter = profile ? profile.nozzle_diameter : modalDiameter;
+
     // For editing or single extruder: just save one profile
     if (profile || selectedExtruders.length === 1) {
       const payload = {
         name: name,
         k_value: formattedKValue,
         filament_id: filamentId,
-        nozzle_id: nozzleId,
-        nozzle_diameter: modalDiameter,
+        nozzle_id: editNozzleId,
+        nozzle_diameter: editDiameter,
         extruder_id: profile ? profile.extruder_id : selectedExtruders[0],
         setting_id: profile?.setting_id,
         slot_id: profile?.slot_id ?? 0,
@@ -508,7 +525,7 @@ function KProfileModal({
                     if (!profile && filamentId && !name) {
                       const selectedFilament = knownFilaments.find(f => f.id === filamentId);
                       if (selectedFilament) {
-                        const flowLabel = newNozzleType === 'HS00' ? 'HF' : 'S';
+                        const flowLabel = newNozzleType === 'HH00' ? 'HF' : 'S';
                         setName(`${flowLabel} ${selectedFilament.name}`);
                       }
                     }
@@ -516,6 +533,12 @@ function KProfileModal({
                   disabled={!!profile}
                   className={`w-full px-3 py-2 bg-bambu-dark border border-bambu-dark-tertiary rounded-lg text-white focus:border-bambu-green focus:outline-none ${profile ? 'opacity-60 cursor-not-allowed' : ''}`}
                 >
+                  {/* Only reachable when editing a profile the printer
+                      reported without a nozzle_id — the select is disabled
+                      there, so this is a readout, not a choice. */}
+                  {nozzleType === '' && (
+                    <option value="">{t('kProfiles.modal.flowTypeNotReported')}</option>
+                  )}
                   <option value="HH00">{t('kProfiles.modal.highFlow')}</option>
                   <option value="HS00">{t('kProfiles.modal.standard')}</option>
                 </select>
@@ -865,6 +888,21 @@ export function KProfilesView() {
     return builtinFilamentMap.get(profile.filament_id) || extractFilamentName(profile.name);
   }, [builtinFilamentMap]);
 
+  // Whether the printer reports a nozzle_id at all. Single-nozzle models omit
+  // it from every extrusion_cali_get entry (#1748), so a flow-type filter there
+  // could only ever match nothing — hide it instead of offering a control that
+  // silently empties the list.
+  const hasFlowTypeInfo = React.useMemo(
+    () => (kprofiles?.profiles ?? []).some((p) => getFlowTypeLabel(p.nozzle_id) !== ''),
+    [kprofiles?.profiles]
+  );
+
+  // Don't strand the list behind a filter whose control just disappeared
+  // (switching printers, or a refetch that no longer carries nozzle ids).
+  useEffect(() => {
+    if (!hasFlowTypeInfo) setFlowTypeFilter('all');
+  }, [hasFlowTypeInfo]);
+
   // Filter and sort profiles
   // Note: nozzle diameter filtering is done server-side via MQTT request
   const filteredProfiles = React.useMemo(() => {
@@ -1002,7 +1040,10 @@ export function KProfilesView() {
               name: p.name,
               k_value: parseFloat(p.k_value).toFixed(6),
               filament_id: p.filament_id,
-              nozzle_id: p.nozzle_id || `HH00-${nozzleDiameter}`,
+              // Keep an absent nozzle_id absent. Exports from single-nozzle
+              // printers carry none (#1748), and HH00 vs HS00 is a coin flip
+              // we'd be writing to the printer as if it were fact.
+              nozzle_id: p.nozzle_id || '',
               nozzle_diameter: p.nozzle_diameter || nozzleDiameter,
               extruder_id: p.extruder_id ?? 0,
               slot_id: 0, // Always create new
@@ -1248,17 +1289,19 @@ export function KProfilesView() {
             </select>
           </div>
         )}
-        <div className="w-32">
-          <select
-            value={flowTypeFilter}
-            onChange={(e) => setFlowTypeFilter(e.target.value as FlowTypeFilter)}
-            className="w-full px-3 py-2 bg-bambu-dark border border-bambu-dark-tertiary rounded-lg text-white focus:border-bambu-green focus:outline-none"
-          >
-            <option value="all">{t('kProfiles.allFlow')}</option>
-            <option value="hf">{t('kProfiles.hfOnly')}</option>
-            <option value="s">{t('kProfiles.sOnly')}</option>
-          </select>
-        </div>
+        {hasFlowTypeInfo && (
+          <div className="w-32">
+            <select
+              value={flowTypeFilter}
+              onChange={(e) => setFlowTypeFilter(e.target.value as FlowTypeFilter)}
+              className="w-full px-3 py-2 bg-bambu-dark border border-bambu-dark-tertiary rounded-lg text-white focus:border-bambu-green focus:outline-none"
+            >
+              <option value="all">{t('kProfiles.allFlow')}</option>
+              <option value="hf">{t('kProfiles.hfOnly')}</option>
+              <option value="s">{t('kProfiles.sOnly')}</option>
+            </select>
+          </div>
+        )}
         <div className="w-32">
           <select
             value={sortOption}