New Webserver and WebApp (#942)

* Replace the WCF webserver with an ASP.NET Core webserver (VocaluxeWeb)

- New project VocaluxeWeb: ASP.NET Core 2.3 (Kestrel) on .NET Framework 4.8.1, HTTP or HTTPS
  with a self-signed certificate, REST API (/api/v1) with Swagger, live events (Server-Sent Events)
- Access to the game only through IVocaluxeRemote; requests run on the main thread once per frame
- Sessions with roles (guest, player, admin) and configurable permissions, PINs hashed with PBKDF2
- Queue as a playlist with requesters and singers, fair order (one song per person and round)
- Admin: settings, server status, logged-in devices, activate/deactivate and delete profiles
- Profile pictures: own photo or one of the Vocaluxe avatars
- Game: WebApp queue screen (song options, playlist group) to start the next song with the chosen
  singers, return to it after singing, warning when the webserver is off, remote keyboard
- Old WCF server, WebserverInitalConfig and URL reservations removed; libraries moved to libs/managed
- Unit tests for PIN hashing, settings and permissions, queue order and device names
- AppVeyor: Visual Studio 2022 image and Node.js 24 (the build compiles the WebApp)
- Documentation in VocaluxeWeb/README.md

* New WebApp (Vue 3, TypeScript, Vite) replacing the old jQuery Mobile website

- Login with profile and PIN, create profiles
- Songs with search, filters, sorting and 30 second previews
- Queue: add songs with game mode, audio and singers, edit, reorder, start in the game
- Playlists: create, edit, add to the queue
- Now playing with live updates, remote control and keyboard
- Players: own profile with picture (photo or Vocaluxe avatar), roles for admins
- Admin settings: permissions, server status, devices, profiles
- Help page, responsive layout for phones, tablets and desktops, light and dark mode
- Texts in WebApp/src/locales/en.json, translated with Transifex
- Old website and PhoneGap config removed

---------

Co-authored-by: Florian Ostertag <flokuep@users.noreply.github.com>

VocaluxeWeb/Services/CWebSettingsStore.cs

@@ -0,0 +1,152 @@
+#region license
+// This file is part of Vocaluxe.
+//
+// Vocaluxe is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Vocaluxe is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Vocaluxe. If not, see <http://www.gnu.org/licenses/>.
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Security.Cryptography;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Converters;
+using VocaluxeWeb.Contracts;
+using VocaluxeWeb.Remote;
+
+namespace VocaluxeWeb.Services
+{
+    /// Settings of the webserver, stored as JSON next to the game's data. Admins always have every permission.
+    public sealed class CWebSettings
+    {
+        public bool AllowProfileCreation = true;
+        public string QueuePlaylistName = "WebApp Queue";
+
+        [JsonProperty(ItemConverterType = typeof(StringEnumConverter))]
+        public List<EPermission> GuestPermissions = new List<EPermission> { EPermission.AddToQueue };
+
+        [JsonProperty(ItemConverterType = typeof(StringEnumConverter))]
+        public List<EPermission> PlayerPermissions = new List<EPermission>
+        {
+            EPermission.AddToQueue,
+            EPermission.UseKeyboard,
+            EPermission.EditPlaylists,
+            EPermission.EditOwnProfile,
+            EPermission.CreateProfiles
+        };
+
+        public CWebSettings Clone()
+        {
+            var clone = (CWebSettings)MemberwiseClone();
+            clone.GuestPermissions = GuestPermissions.ToList();
+            clone.PlayerPermissions = PlayerPermissions.ToList();
+            return clone;
+        }
+
+        public IList<EPermission> GetPermissions(ERemoteRole role)
+        {
+            switch (role)
+            {
+                case ERemoteRole.Admin:
+                    return (EPermission[])Enum.GetValues(typeof(EPermission));
+                case ERemoteRole.Player:
+                    return PlayerPermissions;
+                default:
+                    return GuestPermissions;
+            }
+        }
+    }
+
+    public sealed class CWebSettingsStore
+    {
+        private readonly string _Path;
+        private readonly object _Lock = new object();
+        private CWebSettings _Settings;
+
+        public CWebSettingsStore(string path)
+        {
+            _Path = path;
+            _Settings = _Load();
+        }
+
+        /// A copy of the current settings.
+        public CWebSettings Current
+        {
+            get
+            {
+                lock (_Lock)
+                {
+                    return _Settings.Clone();
+                }
+            }
+        }
+
+        public void Update(Action<CWebSettings> change)
+        {
+            lock (_Lock)
+            {
+                var settings = _Settings.Clone();
+                change(settings);
+                _Settings = settings;
+                _Save(settings);
+            }
+        }
+
+        private CWebSettings _Load()
+        {
+            CWebSettings settings = null;
+            if (!string.IsNullOrEmpty(_Path) && File.Exists(_Path))
+            {
+                try
+                {
+                    settings = JsonConvert.DeserializeObject<CWebSettings>(File.ReadAllText(_Path));
+                }
+                catch (Exception)
+                {
+                    //Broken file, start with the default settings
+                }
+            }
+
+            return settings ?? new CWebSettings();
+        }
+
+        private void _Save(CWebSettings settings)
+        {
+            if (string.IsNullOrEmpty(_Path))
+            {
+                return;
+            }
+
+            var directory = Path.GetDirectoryName(_Path);
+            if (!string.IsNullOrEmpty(directory))
+            {
+                Directory.CreateDirectory(directory);
+            }
+
+            File.WriteAllText(_Path, JsonConvert.SerializeObject(settings, Formatting.Indented));
+        }
+
+        /// Random URL-safe token with the given number of bytes of entropy.
+        public static string CreateToken(int bytes)
+        {
+            var buffer = new byte[bytes];
+            using (var rng = RandomNumberGenerator.Create())
+            {
+                rng.GetBytes(buffer);
+            }
+
+            return Convert.ToBase64String(buffer).TrimEnd('=').Replace('+', '-').Replace('/', '_');
+        }
+    }
+}