feat: explorer API, wallet, CCIP scripts, and config refresh

- Backend REST/gateway/track routes, analytics, Blockscout proxy paths.
- Frontend wallet and liquidity surfaces; MetaMask token list alignment.
- Deployment docs, verification scripts, address inventory updates.

Check: go build ./... under backend/ (pass).
Made-with: Cursor

frontend/src/utils/format.ts

@@ -0,0 +1,30 @@
+const WEI_DECIMALS = 18n
+
+export function formatWeiAsEth(value: string, fractionDigits = 4): string {
+  try {
+    const normalizedDigits = Math.max(0, Math.min(18, fractionDigits))
+    const wei = BigInt(value)
+    const divisor = 10n ** WEI_DECIMALS
+    const whole = wei / divisor
+    const fraction = wei % divisor
+
+    if (normalizedDigits === 0) {
+      return `${whole.toString()} ETH`
+    }
+
+    const scale = 10n ** (WEI_DECIMALS - BigInt(normalizedDigits))
+    const truncatedFraction = fraction / scale
+    const paddedFraction = truncatedFraction
+      .toString()
+      .padStart(normalizedDigits, '0')
+      .replace(/0+$/, '')
+
+    if (!paddedFraction) {
+      return `${whole.toString()} ETH`
+    }
+
+    return `${whole.toString()}.${paddedFraction} ETH`
+  } catch {
+    return '0 ETH'
+  }
+}