feat: add across action provider (ts)

[phdargen]

Description

Adds new action provider to perform cross-chain interactions via the Across protocol.
Across SDK is added as new dependency.

Implements bridge_token action to bridge from connected chain to another evm chain.
Supports native ETH and ERC-20 transfers (as long as supported by Across)

Tests

• Added unit tests
• Tested prompts

Chatbot: typescript/examples/langchain-cdp-chatbot/chatbot.ts
Network: Sepolia
Setup: Fauceted with 1 USDC and ETH

Prompt: bridge to chain 84532, amount 0.001 ETH, receipienct 0xb7f17bF94DBa50077be037CDc279a868f82D86C2

-------------------
Successfully deposited tokens:
- From: Chain 11155111 (Sepolia)
- To: Chain 84532 (Base Sepolia)
- Token: ETH (0xfFf9976782d46CC05630D1f6eBAb18b2324d6B14)
- Input Amount: 0.001 ETH
- Output Amount: 0.000989964511456042 ETH
- Recipient: 0xb7f17bF94DBa50077be037CDc279a868f82D86C2
- Transaction Hash for deposit: 0xde3327c2be34931343fa9ceae2a89c0d56a9feb398ded5a60dd7e49e9baa0889
-------------------

Prompt: bridge to chain 84532, amount 0.1 usdc, receipienct 0xb7f17bF94DBa50077be037CDc279a868f82D86C2, max slippage 3%
The bridging transaction was successful! Here are the details:

- **From Chain:** 11155111 (Sepolia)
- **To Chain:** 84532 (Base Sepolia)
- **Token:** USDC
- **Input Amount:** 0.1 USDC
- **Output Amount:** 0.098182 USDC
- **Recipient:** 0xb7f17bF94DBa50077be037CDc279a868f82D86C2
- **Transaction Hash for Approval:** 0x33575547e8031d3223e63dbc2e82fbc307b1391bd9c6379c8a91952b47024e92
- **Transaction Hash for Deposit:** 0x797f7d27e820f1832f994b6a6218118803fbc500f18caa70179811b4be21b2aa

Checklist

• Added documentation to all relevant README.md files
• Added a changelog entry

[cb-heimdall]

🟡 Heimdall Review Status

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Reviews	🟡 0/1	Denominator calculation Show calculation 1 if user is bot 0 1 if user is external 0 From .codeflow.yml 1 Additional review requirements Show calculation Max 0 0 From CODEOWNERS 0 Global minimum 0 Max 1 1 1 if commit is unverified 0 Sum 1

[KanishkKhurana]

left one comment around manual txn simulation and executing the deposit txn.

overall, really good job from an Across Protocol integration POV

[KanishkKhurana]

Diving deep into the logic behind this, are we simulating txn and executing the deposit fn manually because there's no way to trigger a wallet extension ?
I ask because we have the executeQuote function which will be able to wrap complexities around txn simulation and executing the deposit txn.

overall this is a stellar job. thank you for putting in the effort here!

[phdargen]

Hi @KanishkKhurana , thank you for the feedback!

I initially used executeQuote which would indeed simplify the process. This works fine until progress.step === "deposit" is succesful but then throws errors in the progress.step === "fill" step. I suspect this is because no RPC was available for the destination chain.

Now thinking about it again, it might work when we just add the destination chain to the viem client. It would certainly be nice to also return the fill txHash. A bit busy atm but will give it a try in the next days and get back to you