fix: parse version.json instead of version.txt in Program.cs

- CI/CD generates version.json (JSON format) but Program.cs was parsing version.txt
- Update version loading to read from version.json
- Add error handling for JSON parsing

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

TaxBaik.Web/Program.cs

@@ -85,16 +85,21 @@ builder.Services.AddApplication();
 
 // Register version info
 var versionInfo = new VersionInfo();
-var versionFilePath = Path.Combine(AppContext.BaseDirectory, "wwwroot", "version.txt");
-if (File.Exists(versionFilePath))
+var versionJsonPath = Path.Combine(AppContext.BaseDirectory, "wwwroot", "version.json");
+if (File.Exists(versionJsonPath))
 {
-    var lines = File.ReadAllLines(versionFilePath);
-    foreach (var line in lines)
+    try
     {
-        if (line.StartsWith("Version:"))
-            versionInfo.Version = line.Substring("Version:".Length).Trim();
-        else if (line.StartsWith("Built:"))
-            versionInfo.Built = line.Substring("Built:".Length).Trim();
+        var json = System.Text.Json.JsonDocument.Parse(File.ReadAllText(versionJsonPath));
+        var root = json.RootElement;
+        if (root.TryGetProperty("version", out var versionProp))
+            versionInfo.Version = versionProp.GetString() ?? "unknown";
+        if (root.TryGetProperty("built", out var builtProp))
+            versionInfo.Built = builtProp.GetString() ?? "unknown";
+    }
+    catch (Exception ex)
+    {
+        Console.WriteLine($"Warning: Failed to parse version.json: {ex.Message}");
     }
 }
 builder.Services.AddSingleton(versionInfo);