Function encode_v3_path_exact_output 

pub fn encode_v3_path_exact_output(
    token_in: Address,
    path: &[SwapHop],
) -> Result<Vec<u8>, Web3Error>

Encodes a multi-hop swap path for Uniswap V3’s exactOutput function.

For exactOutput swaps, the path must be encoded in reverse order (tokenOut first, tokenIn last). This function takes a path in the logical order (tokenIn to tokenOut) and reverses it automatically.

Arguments

• token_in - The input token address (first token in the logical path)
• path - The swap path as a sequence of (token, fee) hops

Returns

The encoded path as bytes in reversed order, suitable for exactOutput calls