chore: add TODO and stubs for Robinhood token-by-contract support

ROBINHOOD_TOKEN_SUPPORT.md

@@ -0,0 +1,19 @@
+# ROBINHOOD_TOKEN_SUPPORT
+
+Goal: support any token on the Robinhood chain by contract address.
+
+Tasks:
+1. Add Robinhood chain config (chainId, RPC endpoint, block explorer URL).
+2. Implement token resolver:
+   - Given rpcUrl and contract address, call standard ERC-20 metadata: name(), symbol(), decimals().
+   - Return { name, symbol, decimals, address, logo? } and a status for non-ERC20 tokens.
+3. Validate and checksum addresses; handle invalid contracts gracefully.
+4. Add caching, rate-limiting and retries for RPC calls.
+5. Integrate resolver into token lookup flows (backend and UI).
+6. Add unit tests and an integration test against a public Robinhood RPC or testnet.
+7. Docs: usage, environment variables for RPC, and security notes.
+
+Notes:
+- Use ethers.js (recommended) or web3.js.
+- Fall back to tokenlist lookup or a metadata service if metadata calls fail.
+- Add feature flag / UI input for manual contract address when chain = Robinhood.

src/chains/robinhood.ts

@@ -0,0 +1,6 @@
+export const robinhoodChain = {
+  name: 'Robinhood',
+  chainId: 0x0, // TODO: replace with actual chainId (decimal or hex)
+  rpc: process.env.ROBINHOOD_RPC || 'https://rpc.robinhood.example', // TODO: real RPC
+  explorer: 'https://explorer.robinhood.example', // TODO
+};

src/tokens/resolveByContract.ts

@@ -0,0 +1,24 @@
+import { ethers } from 'ethers';
+
+const ERC20_ABI = [
+  'function name() view returns (string)',
+  'function symbol() view returns (string)',
+  'function decimals() view returns (uint8)',
+];
+
+export async function resolveTokenByContract(rpcUrl: string, address: string) {
+  const provider = new ethers.providers.JsonRpcProvider(rpcUrl);
+  const contract = new ethers.Contract(address, ERC20_ABI, provider);
+
+  try {
+    const [name, symbol, decimals] = await Promise.all([
+      contract.name(),
+      contract.symbol(),
+      contract.decimals(),
+    ]);
+    return { address, name, symbol, decimals: Number(decimals) };
+  } catch (err) {
+    // Non-ERC20 or call failure — return a structured error/status
+    return { address, error: 'metadata_unavailable', details: String(err) };
+  }
+}

tests/resolveByContract.test.ts

@@ -0,0 +1,11 @@
+import { resolveTokenByContract } from '../src/tokens/resolveByContract';
+
+describe('resolveTokenByContract', () => {
+  it('returns token metadata for a valid ERC20 on Robinhood', async () => {
+    // TODO: use a real test RPC or a mocked provider
+    const rpc = process.env.ROBINHOOD_RPC || 'https://rpc.robinhood.example';
+    const result = await resolveTokenByContract(rpc, '0x0000000000000000000000000000000000000000');
+    // replace assertions once a real test token is selected
+    expect(result).toHaveProperty('address');
+  });
+});