refactor: comply with tx3 sdk spec

README.md

@@ -0,0 +1,75 @@
+# tx3-sdk
+
+TypeScript/JavaScript SDK for the [Tx3](https://tx3.land) transaction protocol. Load compiled `.tii` artifacts at runtime, resolve and sign transactions through TRP, and poll for on-chain confirmation — all from a single builder chain.
+
+## Install
+
+```bash
+npm install tx3-sdk
+```
+
+## Quick start
+
+```ts
+import {
+  Tx3Client,
+  Protocol,
+  TrpClient,
+  Party,
+  Ed25519Signer,
+  PollConfig,
+} from "tx3-sdk";
+
+// 1. Load the protocol (compiled .tii file)
+const protocol = await Protocol.fromFile("./transfer.tii");
+
+// 2. Connect to a TRP server
+const trp = new TrpClient({ endpoint: "http://localhost:3000/rpc" });
+
+// 3. Set up signers and parties
+const signer = Ed25519Signer.fromHex("addr_test1...", "deadbeef...");
+
+const tx3 = new Tx3Client(protocol, trp)
+  .withProfile("preprod")
+  .withParty("sender", Party.signer(signer))
+  .withParty("receiver", Party.address("addr_test1..."));
+
+// 4. Build, sign, submit, and wait
+const status = await tx3
+  .tx("transfer")
+  .arg("quantity", 10_000_000n)
+  .resolve()
+  .then((r) => r.sign())
+  .then((s) => s.submit())
+  .then((sub) => sub.waitForConfirmed(PollConfig.default()));
+
+console.log(status.stage); // "confirmed"
+```
+
+## Subpath imports
+
+The package exposes granular entry points for tree-shaking or when you only need a subset:
+
+```ts
+import { TrpClient } from "tx3-sdk/trp";
+import { Protocol } from "tx3-sdk/tii";
+import { CardanoSigner } from "tx3-sdk/signer";
+```
+
+## Browser usage
+
+`Protocol.fromFile` uses `node:fs` and is Node-only. In the browser, fetch the `.tii` JSON yourself:
+
+```ts
+const protocol = Protocol.fromString(await (await fetch("/transfer.tii")).text());
+```
+
+## Compatibility
+
+- **TRP protocol:** v1beta0
+- **TII schema:** v1beta0
+- **Runtime:** Node.js 18+, modern browsers (ESM), Bun, Deno
+
+## License
+
+Apache-2.0