cleanup: remove BlackListManager, unify HttpClient with static shared instance, deduplicate IPC encryption

- Delete deprecated BlackListManager singleton, extract IBlackListMatcher to own file
- Add HttpClientProvider with static shared HttpClient (no DI dependency)
- Replace all new HttpClient() with HttpClientProvider.Shared
- Extract IpcEncryption shared AES utility used by Environments and IProcessInfoProvider
- Fix Muti -> Multi file name typo (4 event args)
- Delete stale net9.0 bin/obj and ConfiginfoBuilder-Example.cs

Closes #419

Author: JusterZhu

src/c#/GeneralUpdate.Core/Configuration/ConfiginfoBuilder-Example.cs

@@ -2,17 +2,17 @@
 using System.IO;
 using System.Security.Cryptography;
 using System.Text;
+using GeneralUpdate.Core.Ipc;
 
 namespace GeneralUpdate.Core.Configuration;
 
 /// <summary>
 /// Secure IPC environment variable provider.
 /// AES-encrypted temp files in a dedicated subdirectory, auto-deleted after read.
+/// Encryption is delegated to <see cref="IpcEncryption"/>.
 /// </summary>
 public static class Environments
 {
-    // Fixed key/IV derived from a constant — not crypto-grade, but sufficient for
-    // ephemeral IPC where the file lives < 1 second and is in a per-user directory.
     private static readonly byte[] _aesKey = SHA256.Create()
         .ComputeHash(Encoding.UTF8.GetBytes("GeneralUpdate.IPC.EnvironmentProvider.v1"));
     private static readonly byte[] _aesIV = new byte[16] { 0x47, 0x55, 0x50, 0x44, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
@@ -31,33 +31,13 @@ public static void SetEnvironmentVariable(string key, string value)
     {
         var filePath = Path.Combine(IpcDir, $"{key}.enc");
         var plainBytes = Encoding.UTF8.GetBytes(value);
-        using var aes = Aes.Create();
-        aes.Key = _aesKey;
-        aes.IV = _aesIV;
-        using var encryptor = aes.CreateEncryptor();
-        var encrypted = encryptor.TransformFinalBlock(plainBytes, 0, plainBytes.Length);
-        File.WriteAllBytes(filePath, encrypted);
+        IpcEncryption.EncryptToFile(plainBytes, filePath, _aesKey, _aesIV);
     }
 
     public static string GetEnvironmentVariable(string key)
     {
         var filePath = Path.Combine(Path.GetTempPath(), "GeneralUpdate", "ipc", $"{key}.enc");
-        if (!File.Exists(filePath))
-            return string.Empty;
-
-        try
-        {
-            var encrypted = File.ReadAllBytes(filePath);
-            using var aes = Aes.Create();
-            aes.Key = _aesKey;
-            aes.IV = _aesIV;
-            using var decryptor = aes.CreateDecryptor();
-            var plainBytes = decryptor.TransformFinalBlock(encrypted, 0, encrypted.Length);
-            return Encoding.UTF8.GetString(plainBytes);
-        }
-        finally
-        {
-            try { File.Delete(filePath); } catch { /* best-effort cleanup */ }
-        }
+        var plainBytes = IpcEncryption.DecryptFromFile(filePath, _aesKey, _aesIV);
+        return plainBytes != null ? Encoding.UTF8.GetString(plainBytes) : string.Empty;
     }
 }

src/c#/GeneralUpdate.Core/Configuration/Environments.cs

@@ -2,7 +2,7 @@
 
 namespace GeneralUpdate.Core.FileSystem;
 
-/// <summary>Built-in default blacklist items — previously hardcoded in BlackListManager.</summary>
+/// <summary>Built-in default blacklist items.</summary>
 public static class BlackListDefaults
 {
     /// <summary>Default blacklisted files (system DLLs that ship with the runtime).</summary>

…rgs/MutiAllDownloadCompletedEventArgs.cs …gs/MultiAllDownloadCompletedEventArgs.cssrc/c#/GeneralUpdate.Core/Download/MultiEventArgs/MutiAllDownloadCompletedEventArgs.cs renamed to src/c#/GeneralUpdate.Core/Download/MultiEventArgs/MultiAllDownloadCompletedEventArgs.cs src/c#/GeneralUpdate.Core/Download/MultiEventArgs/MutiAllDownloadCompletedEventArgs.cs renamed to src/c#/GeneralUpdate.Core/Download/MultiEventArgs/MultiAllDownloadCompletedEventArgs.cs

@@ -0,0 +1,11 @@
+using System.Collections.Generic;
+
+namespace GeneralUpdate.Core.FileSystem;
+
+/// <summary>Matches files/directories against a blacklist configuration.</summary>
+public interface IBlackListMatcher
+{
+    bool IsBlacklisted(string relativeFilePath);
+    bool IsBlacklistedFormat(string extension);
+    bool ShouldSkipDirectory(string directoryName);
+}

…ntArgs/MutiDownloadCompletedEventArgs.cs …tArgs/MultiDownloadCompletedEventArgs.cssrc/c#/GeneralUpdate.Core/Download/MultiEventArgs/MutiDownloadCompletedEventArgs.cs renamed to src/c#/GeneralUpdate.Core/Download/MultiEventArgs/MultiDownloadCompletedEventArgs.cs src/c#/GeneralUpdate.Core/Download/MultiEventArgs/MutiDownloadCompletedEventArgs.cs renamed to src/c#/GeneralUpdate.Core/Download/MultiEventArgs/MultiDownloadCompletedEventArgs.cs

@@ -14,7 +14,7 @@ public sealed class StorageManager
         private long _fileCount = 0;
         public const string DirectoryName = "app-";
 
-        /// <summary>Optional blacklist matcher. When set, takes precedence over BlackListManager.</summary>
+        /// <summary>Optional blacklist matcher. Must be set before any file operation.</summary>
         public static IBlackListMatcher? BlackListMatcher { get; set; }
 
         private ComparisonResult ComparisonResult { get; set; }
@@ -267,9 +267,7 @@ private IEnumerable<FileNode> ReadFileNode(string path, string rootPath = null)
 
             foreach (var subPath in Directory.EnumerateFiles(path))
             {
-#pragma warning disable CS0618 // Obsolete fallback
-                if ((BlackListMatcher ?? BlackListManager.Instance).IsBlacklisted(subPath)) continue;
-#pragma warning restore CS0618
+                if (BlackListMatcher != null && BlackListMatcher.IsBlacklisted(subPath)) continue;
 
                 var hashAlgorithm = new Sha256HashAlgorithm();
                 var hash = hashAlgorithm.ComputeHash(subPath);
@@ -288,9 +286,7 @@ private IEnumerable<FileNode> ReadFileNode(string path, string rootPath = null)
 
             foreach (var subPath in Directory.EnumerateDirectories(path))
             {
-#pragma warning disable CS0618 // Obsolete fallback
-                if ((BlackListMatcher ?? BlackListManager.Instance).ShouldSkipDirectory(subPath)) continue;
-#pragma warning restore CS0618
+                if (BlackListMatcher != null && BlackListMatcher.ShouldSkipDirectory(subPath)) continue;
                 resultFiles.AddRange(ReadFileNode(subPath, rootPath));
             }