Add QUSD (QVTX USD) stablecoin — BSC, Polygon, Base, Arbitrum

[quant-oss]

Adds QVTX USD (QUSD), a fiat-backed USD stablecoin, so it displays correctly in MetaMask on the chains it's deployed to.

• Contract (same address on every chain): 0xb57BF3C50F20096723B46645f741f632AEF220FA
• Symbol: QUSD · Decimals: 18 · erc20: true
• Chains: BNB Smart Chain (56), Polygon (137), Base (8453), Arbitrum (42161)
• 100% cover enforced on-chain per mint (backingBps() == 10000), redeemable at par.
• Website: https://qusd.quantvestrix.io · Proof of reserve: https://qusd.quantvestrix.io/v1/proof-of-reserve

Each chain has a metadata/eip155:<chainId>/erc20:<address>.json (erc20:true) + matching icons/…svg.

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Note

Low Risk
Adds static token metadata and icons only; no application or on-chain logic changes.

Overview
Registers QVTX USD (QUSD) at 0xb57BF3C50F20096723B46645f741f632AEF220FA for MetaMask token display on BNB Smart Chain (56), Polygon (137), Base (8453), and Arbitrum (42161).

Each chain gets a new metadata/eip155:<chainId>/erc20:<address>.json entry (name: QVTX USD, symbol: QUSD, decimals: 18, erc20: true) plus a matching green “Q” dollar SVG under icons/.

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