Add storage-proto build.rs and readme (#18353)

* Use build.rs for storage-proto generation

* Add readme

* Single use statements

storage-proto/build.rs

@@ -0,0 +1,24 @@
+fn main() -> Result<(), std::io::Error> {
+    let manifest_dir = std::path::PathBuf::from(env!("CARGO_MANIFEST_DIR"));
+
+    let out_dir = manifest_dir.join("proto");
+    let proto_files = manifest_dir.join("src");
+
+    std::fs::create_dir_all(out_dir.clone())?;
+
+    println!("Protobuf directory: {}", proto_files.display());
+    println!("output directory: {}", out_dir.display());
+
+    tonic_build::configure()
+        .build_client(true)
+        .build_server(false)
+        .format(true)
+        .out_dir(&out_dir)
+        .compile(
+            &[
+                proto_files.join("confirmed_block.proto"),
+                proto_files.join("transaction_by_addr.proto"),
+            ],
+            &[proto_files],
+        )
+}