[SDK] Feature: Export prepareMethod (#5439)

CNCT-2381

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## PR-Codex overview
This PR adds a new export to the `contract.ts` file, enhancing the available utilities for contract interactions.

### Detailed summary
- Added export for `prepareMethod` from `../utils/abi/prepare-method.js`.

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Author: gregfromstl

packages/thirdweb/src/exports/contract.ts

@@ -40,5 +40,6 @@ export {
   type PrepareDirectDeployTransactionOptions,
 } from "../contract/deployment/deploy-with-abi.js";
 export { prepareAutoFactoryDeployTransaction } from "../contract/deployment/deploy-via-autofactory.js";
+export { prepareMethod } from "../utils/abi/prepare-method.js";
 
 export { getCompilerMetadata } from "../contract/actions/get-compiler-metadata.js";