stabilizaiton work - projects rework for maintenanceability and ui livening

src/__Libraries/StellaOps.Provcache/Export/BundleChunk.cs

@@ -0,0 +1,39 @@
+using System.Text.Json.Serialization;
+
+namespace StellaOps.Provcache;
+
+/// <summary>
+/// Chunk included in the bundle with base64-encoded blob.
+/// </summary>
+public sealed record BundleChunk
+{
+    /// <summary>
+    /// Zero-based chunk index.
+    /// </summary>
+    [JsonPropertyName("index")]
+    public required int Index { get; init; }
+
+    /// <summary>
+    /// SHA256 hash for verification.
+    /// </summary>
+    [JsonPropertyName("hash")]
+    public required string Hash { get; init; }
+
+    /// <summary>
+    /// Size in bytes.
+    /// </summary>
+    [JsonPropertyName("size")]
+    public required int Size { get; init; }
+
+    /// <summary>
+    /// MIME type.
+    /// </summary>
+    [JsonPropertyName("contentType")]
+    public required string ContentType { get; init; }
+
+    /// <summary>
+    /// Base64-encoded chunk data.
+    /// </summary>
+    [JsonPropertyName("data")]
+    public required string Data { get; init; }
+}