Initial import of the CBDDC codebase with docs and tests. Add a .NET-focused gitignore to keep generated artifacts out of source control.

src/ZB.MOM.WW.CBDDC.Network/sync.proto

@@ -0,0 +1,117 @@
+syntax = "proto3";
+
+package ZB.MOM.WW.CBDDC.Network.Proto;
+
+option csharp_namespace = "ZB.MOM.WW.CBDDC.Network.Proto";
+
+message HandshakeRequest {
+  string node_id = 1;
+  string auth_token = 2;
+  repeated string supported_compression = 3; // v4
+  repeated string interesting_collections = 4; // v5
+}
+
+message HandshakeResponse {
+  string node_id = 1;
+  bool accepted = 2;
+  string selected_compression = 3; // v4
+  repeated string interesting_collections = 4; // v5
+}
+
+message GetClockRequest {
+}
+
+message ClockResponse {
+  int64 hlc_wall = 1;
+  int32 hlc_logic = 2;
+  string hlc_node = 3;
+}
+
+message GetVectorClockRequest {
+}
+
+message VectorClockResponse {
+  repeated VectorClockEntry entries = 1;
+}
+
+message VectorClockEntry {
+  string node_id = 1;
+  int64 hlc_wall = 2;
+  int32 hlc_logic = 3;
+}
+
+message PullChangesRequest {
+  int64 since_wall = 1;
+  int32 since_logic = 2;
+  string since_node = 3;
+  repeated string collections = 4; // v5: Filter by collection
+}
+
+message ChangeSetResponse {
+  repeated ProtoOplogEntry entries = 1;
+}
+
+message PushChangesRequest {
+  repeated ProtoOplogEntry entries = 1;
+}
+
+message GetChainRangeRequest { 
+  string start_hash = 1; 
+  string end_hash = 2; 
+}
+
+message ChainRangeResponse { 
+  repeated ProtoOplogEntry entries = 1; 
+  bool snapshot_required = 2;
+}
+
+message AckResponse {
+  bool success = 1;
+  bool snapshot_required = 2;
+}
+
+message ProtoOplogEntry {
+  string collection = 1;
+  string key = 2;
+  string operation = 3; // "Put" or "Delete"
+  string json_data = 4;
+  int64 hlc_wall = 5;
+  int32 hlc_logic = 6;
+  string hlc_node = 7;
+  string hash = 8;
+  string previous_hash = 9;
+}
+
+message GetSnapshotRequest {
+}
+
+message SnapshotChunk {
+    bytes data = 1;
+    bool is_last = 2;
+}
+
+// Enum for wire framing (1 byte)
+enum MessageType {
+  Unknown = 0;
+  HandshakeReq = 1;
+  HandshakeRes = 2;
+  GetClockReq = 3;
+  ClockRes = 4;
+  PullChangesReq = 5;
+  ChangeSetRes = 6;
+  PushChangesReq = 7;
+  AckRes = 8;
+  SecureEnv = 9;
+  GetChainRangeReq = 10;
+  ChainRangeRes = 11;
+  GetVectorClockReq = 12;
+  VectorClockRes = 13;
+  GetSnapshotReq = 14;
+  SnapshotChunkMsg = 15;
+}
+
+message SecureEnvelope {
+  bytes ciphertext = 1; // Encrypted payload
+  bytes nonce = 2;      // IV or Nonce
+  bytes auth_tag = 3;   // HMAC or Auth Tag if using AEAD (optional if concatenated)
+}