feat: implement SavePump/SaveAlarms, fix config round-trip bugs, redesign PDF reports

Config system fixes:
- Implement SavePump() — full XML serialization with insert/update by pump ID
- Add CanBusParameter.ToPumpXml() for legacy P1-P6 pump param format
- Fix LastRotationDirection never loaded in LoadSettings()
- Add SaveAlarms() to ConfigurationService and IConfigurationService
- Remove dead fields AppSettings.Clients and AppSettings.PumpIds

PDF report redesign:
- Professional layout with charts, verdict badges, and tolerance bands
- Add ReportChartRenderer (SVG) and ReportTheme styling constants
- Embed default_logo.png as fallback report logo

Documentation:
- Add gap analysis docs (config validation, ford unlock, missing features)
- Update CLAUDE.md architecture, known gaps, and debt tracking

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

Services/Impl/ConfigurationService.cs

@@ -190,7 +190,84 @@ namespace HC_APTBS.Services.Impl
         /// <inheritdoc/>
         public void SavePump(PumpDefinition pump)
         {
-            _log.Info(LogId, $"SavePump({pump.Id}) — not yet implemented.");
+            try
+            {
+                XDocument xdoc;
+                if (File.Exists(PumpsXml))
+                {
+                    xdoc = XDocument.Load(PumpsXml);
+                }
+                else
+                {
+                    xdoc = new XDocument(new XElement("Config", new XElement("Pumps")));
+                }
+
+                var root = xdoc.Root!;
+                var pumpsNode = root.Element("Pumps");
+                if (pumpsNode == null)
+                {
+                    pumpsNode = new XElement("Pumps");
+                    root.Add(pumpsNode);
+                }
+
+                // Build the <Pump> element mirroring ParsePumpElement's expected format.
+                var xpump = new XElement("Pump",
+                    new XAttribute("id",            pump.Id),
+                    new XAttribute("model",         pump.Model),
+                    new XAttribute("text",          pump.EcuText),
+                    new XAttribute("chaveta",       pump.Chaveta),
+                    new XAttribute("rotation",      pump.Rotation),
+                    new XAttribute("info",          pump.Info),
+                    new XAttribute("preinjection",  pump.HasPreInjection.ToString().ToLowerInvariant()),
+                    new XAttribute("cilinders4",    pump.Is4Cylinder.ToString().ToLowerInvariant()),
+                    new XAttribute("unlock",        pump.UnlockType),
+                    new XAttribute("baudrate",      pump.CanBaudrate == Peak.Can.Basic.TPCANBaudrate.PCAN_BAUD_250K ? "250" : "500"),
+                    new XAttribute("lockangle",     pump.LockAngle.ToString(CultureInfo.InvariantCulture)));
+
+                // PumpID child element — GetPumpIds() finds these via Descendants("PumpID").
+                xpump.Add(new XElement("PumpID", pump.Id));
+
+                // ── Serialise <Params> (pump CAN params use legacy P1–P6 format) ──
+                if (pump.ParametersByName.Count > 0)
+                {
+                    var xparams = new XElement("Params");
+                    foreach (var param in pump.ParametersByName.Values)
+                        xparams.Add(param.ToPumpXml());
+                    xpump.Add(xparams);
+                }
+
+                // ── Serialise <Tests> ──
+                if (pump.Tests.Count > 0)
+                {
+                    var xtests = new XElement("Tests");
+                    foreach (var test in pump.Tests)
+                        xtests.Add(test.ToXml());
+                    xpump.Add(xtests);
+                }
+
+                // ── Find existing pump by ID and replace, or append ──
+                XElement? existing = null;
+                foreach (var child in pumpsNode.Elements("Pump"))
+                {
+                    if (child.Attribute("id")?.Value == pump.Id)
+                    {
+                        existing = child;
+                        break;
+                    }
+                }
+
+                if (existing != null)
+                    existing.ReplaceWith(xpump);
+                else
+                    pumpsNode.Add(xpump);
+
+                xdoc.Save(PumpsXml);
+                _log.Info(LogId, $"SavePump({pump.Id}) — saved to pumps.xml.");
+            }
+            catch (Exception ex)
+            {
+                _log.Error(LogId, $"SavePump({pump.Id}) failed: {ex.Message}");
+            }
         }
 
         // ── IConfigurationService: Clients ────────────────────────────────────────
@@ -241,6 +318,25 @@ namespace HC_APTBS.Services.Impl
             }
         }
 
+        // ── IConfigurationService: Alarms ─────────────────────────────────────────
+
+        /// <inheritdoc/>
+        public void SaveAlarms()
+        {
+            try
+            {
+                var root = new XElement("Alarms");
+                foreach (var alarm in Settings.Alarms)
+                    root.Add(alarm.ToXml());
+                new XDocument(root).Save(AlarmsXml);
+                _log.Info(LogId, "Alarms saved.");
+            }
+            catch (Exception ex)
+            {
+                _log.Error(LogId, $"SaveAlarms failed: {ex.Message}");
+            }
+        }
+
         // ── Pump status definitions ───────────────────────────────────────────────
 
         /// <inheritdoc/>
@@ -349,6 +445,7 @@ namespace HC_APTBS.Services.Impl
                 TryInt(r,    "MaxRpm",            v => _settings.MaxRpm                = v);
                 TryBool(r,   "RightRelayValue",   v => _settings.RightRelayValue       = v);
                 TryBool(r,   "DefaultIgnoreTin",  v => _settings.DefaultIgnoreTin      = v);
+                TryInt(r,    "LastRotationDir",   v => _settings.LastRotationDirection  = (short)v);
                 TryInt(r,    "DaysKeepLogs",      v => _settings.DaysKeepLogs          = v);
                 TryString(r, "CompanyName",       v => _settings.CompanyName           = v);
                 TryString(r, "CompanyInfo",       v => _settings.CompanyInfo           = v);