Initialize CBDD solution and add a .NET-focused gitignore for generated artifacts.

src/CBDD.Core/Storage/IIndexStorage.cs

@@ -0,0 +1,14 @@
+namespace ZB.MOM.WW.CBDD.Core.Storage;
+
+/// <summary>
+/// Narrow storage port for index structures (page operations + allocation only).
+/// </summary>
+internal interface IIndexStorage
+{
+    int PageSize { get; }
+    uint AllocatePage();
+    void FreePage(uint pageId);
+    void ReadPage(uint pageId, ulong? transactionId, Span<byte> destination);
+    void WritePage(uint pageId, ulong transactionId, ReadOnlySpan<byte> data);
+    void WritePageImmediate(uint pageId, ReadOnlySpan<byte> data);
+}