Rename solar integration types to VotronicSolarESP

Renames every type and identifier we built for the solar charge
controller bridge from generic "Solar" naming to the product name
VotronicSolarESP: VanAlignSolarProtocol -> VotronicSolarESPProtocol,
SolarSession -> VotronicSolarESPSession, SolarState ->
VotronicSolarESPState, plus the dependent properties, parameters, and
user-facing discovery/empty-state strings.

Purely a Swift-side rename - the underlying BLE service/characteristic
UUIDs are untouched, so it has no effect on communicating with the
actual firmware. DeviceRole.solar's case name, and DemoData's device
instance variables, are left as-is since they describe the role/demo
device rather than this specific integration code.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

CamperMonitor/Views/DashboardView.swift

@@ -106,7 +106,7 @@ struct DashboardView: View {
             Label("Noch keine Geräte", systemImage: "antenna.radiowaves.left.and.right")
         } description: {
             Text("Füge \(store.activeProfile.map { "„\($0.name)“" } ?? "diesem Fahrzeug") "
-                 + "den Ladebooster, den Solarladeregler und das BMS hinzu.")
+                 + "den Ladebooster, den VotronicSolarESP und das BMS hinzu.")
         } actions: {
             Button("Gerät suchen") { isAddingDevice = true }
                 .buttonStyle(.borderedProminent)