Fixed attached files silently reaching the AI as empty documents (#904)

app/MindWork AI Studio/Tools/ContentStreamErrorDetails.cs

@@ -0,0 +1,55 @@
+using System.Text.Json.Serialization;
+
+namespace AIStudio.Tools;
+
+// ReSharper disable UnusedAutoPropertyAccessor.Global
+// ReSharper disable ClassNeverInstantiated.Global
+public sealed class ContentStreamErrorDetails
+{
+    [JsonPropertyName("code")]
+    public string? Code { get; init; }
+
+    [JsonPropertyName("message")]
+    public string? Message { get; init; }
+
+    /// <summary>
+    /// The page the failure belongs to, when the failure affects a single page only.
+    /// </summary>
+    [JsonPropertyName("page_number")]
+    public int? PageNumber { get; init; }
+
+    /// <summary>
+    /// The format the runtime identified by looking at the content, e.g. when it contradicts the
+    /// file extension.
+    /// </summary>
+    [JsonPropertyName("detected_format")]
+    public string? DetectedFormat { get; init; }
+
+    /// <summary>
+    /// Gets the parsed error code.
+    /// </summary>
+    /// <remarks>
+    /// Codes this version does not know map to <see cref="FileExtractionErrorCode.UNKNOWN"/>
+    /// instead of failing the deserialization. A failed deserialization would turn the reported
+    /// error back into empty file content, which is exactly what we want to avoid here.
+    /// </remarks>
+    [JsonIgnore]
+    public FileExtractionErrorCode ParsedCode => Enum.TryParse<FileExtractionErrorCode>(this.Code, ignoreCase: true, out var parsedCode) ? parsedCode : FileExtractionErrorCode.UNKNOWN;
+
+    /// <summary>
+    /// Gets a value indicating whether this failure affects one part of the file only, while the
+    /// remaining content is still usable.
+    /// </summary>
+    [JsonIgnore]
+    public bool IsPartialFailure => this.ParsedCode is FileExtractionErrorCode.PAGE_EXTRACTION_FAILED;
+
+    /// <summary>
+    /// Gets a value indicating whether this is a notice rather than a failure.
+    /// </summary>
+    /// <remarks>
+    /// A notice tells the user something worth knowing about the file, while the content itself
+    /// was read completely. It must therefore never degrade the outcome of an extraction.
+    /// </remarks>
+    [JsonIgnore]
+    public bool IsNotice => this.ParsedCode is FileExtractionErrorCode.EXTENSION_MISMATCH;
+}