Add EVM/Base support — register ExactEvmScheme alongside Solana

[Morganyyu]

Context

The Vybe x402 gateway (x402-api.vybenetwork.xyz) now advertises payment options on both Solana mainnet and Base mainnet in every 402 challenge — see PR vybenetwork/x402-vybe-gateway#29. The 402 accepts[] array carries two entries:

"accepts": [
  { "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp", "asset": "EPjF...", "payTo": "HJHe...", "extra": { "feePayer": "..." } },
  { "network": "eip155:8453",                            "asset": "0x83358...", "payTo": "0x5a55...", "extra": { "name": "USD Coin", "version": "2" } }
]

Coinbase's CDP facilitator settles both — the gateway is chain-agnostic for verify/settle.

What this SDK is missing

Today src/http.ts registers only ExactSvmScheme:

const scheme = new ExactSvmScheme(signer, ctx.rpcUrl ? { rpcUrl: ctx.rpcUrl } : undefined);
const x402 = new x402Client().register(info.network as any, scheme);

So an EVM-only agent using VybeClient can't pay — x402Client.payOrThrow(...) finds no matching scheme for the EVM entry in accepts[] and falls back to a 402 error. They'd have to drop down to raw @x402/fetch + @x402/evm.

Proposed shape (v0.2.0)

Extend the wallet/client surface so a single VybeClient can hold either or both:

const client = new VybeClient({
  wallet: { solana: loadKeypair(...), evm: { privateKey: "0x..." } },
  // or wallet: loadKeypair(...) for back-compat (still Solana-only)
});

Internally, register both schemes against x402Client:

const x402 = new x402Client();
if (solanaSigner) x402.register("solana:*", new ExactSvmScheme(solanaSigner, opts));
if (evmSigner)    x402.register("eip155:*", new ExactEvmScheme(evmSigner));

The auto-selector picks the first accept whose network matches a registered scheme. Solana clients keep working; EVM clients work for the first time; dual-wallet clients use the gateway's preferred chain (server controls the accepts[] order — Solana first today, configurable).

Out of scope

• Cross-chain routing logic (let server decide via accepts[] order).
• Polygon / Arbitrum / World — same pattern, but the gateway only advertises Base today. Adding them is a one-line gateway change when needed; client SDK should already handle them via eip155:* registration.

Not blocking

The current 0.1.1 release still works fine for Solana flows after the gateway swap. This is a feature-add, not a bug fix.

Acceptance

• VybeClient accepts either Wallet (Solana, back-compat) or { solana?, evm? }
• Both schemes registered against the underlying x402Client when both are provided
• EVM paid call against x402-api.vybenetwork.xyz/v4/markets succeeds on Base (test against Base Sepolia first via the gateway's devnet config)
• README updated with EVM code sample
• No breaking change for existing Solana-only callers

[hjhuang123]

@Morganyyu

我在一家开源商业化公司工作，刷推特的时候看到有人提到这个项目 Star 数很高。

过去 120 小时内新增了约 3769 颗星。follower 数全是 0，following 也是 0，仓库数为 0。

震惊、失望、愤怒、无奈——这几种情绪在我心里交替出现。震惊是因为规模之大超出预期；失望是因为项目本身并非一无是处；愤怒是因为这种行为欺骗了所有人；无奈是因为这种事在圈子里似乎并不罕见。

我写这个 Issue 不是为了声讨任何人。但我觉得有些话应该说出来，不然这件事就会被默默地遮掩过去，而社区里的其他人还蒙在鼓里。

希望维护者能正视这件事：

• 坦诚面对问题
• 把精力放回到代码和文档上
• 对近期 Star 来源做全面核查
• 移除确认的虚假数据

开源的世界不需要虚假的数字，需要真实的代码。
举报工单已送达 GitHub，针对上述违规清理人气流量、关闭项目访问。