[BIP-1]Revised Asset Ratio Structure

This proposal seeks to: Reduce the oBTC asset ratio from 200% to 150%.

Keep in mind that now any amount of BTC minting needs 200% asset ratio to support tunnel capacity. If the proposal is passed, each oBTC will be backed by 100% BTC + 50% ERC-20 assets. In other words, the pledge ratio is adjusted to 50%.

The primary motivating factor for this proposal is that the underlying assets are overly pledged and act as a psychological barrier for people who may want to enter the BoringDAO ecosystem，communities consider replacing pledged assets with decentralized insurance cover.