feat(golden-chain): v2.23 Network Shard Transfer v0.1 — TCP P2P Localhost [Golden Chain #85]

First distributed step: ShardNetwork struct with TCP wire protocol
[64 hash][4 len LE][data]. std.net.Server + tcpConnectToAddress + std.Thread.
5 proofs: roundtrip, multi-shard, 4KB large, VSA fingerprint, SHA-256 integrity.
6/6 network tests green, 50+ total ALL GREEN.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Author: gHashTag

build.zig

@@ -1318,4 +1318,20 @@ pub fn build(b: *std.Build) void {
     const shard_mgr_api_step = b.step("test-shard-mgr-api", "Test ShardManager API (real struct methods)");
     shard_mgr_api_step.dependOn(&run_shard_mgr_api.step);
     test_step.dependOn(&run_shard_mgr_api.step);
+
+    // Generated network transfer tests (from specs/storage/network.vibee)
+    const network_tests = b.addTest(.{
+        .root_module = b.createModule(.{
+            .root_source_file = b.path("generated/network.zig"),
+            .target = target,
+            .optimize = optimize,
+            .imports = &.{
+                .{ .name = "vsa", .module = vsa_mod },
+            },
+        }),
+    });
+    const run_network_tests = b.addRunArtifact(network_tests);
+    const network_step = b.step("test-network-transfer", "Test TCP shard transfer between nodes");
+    network_step.dependOn(&run_network_tests.step);
+    test_step.dependOn(&run_network_tests.step);
 }