Add oracle asset registry

oracle/assets.json

@@ -0,0 +1,63 @@
+{
+  "version": "0.1",
+  "updated": "2026-03-14",
+  "assets": {
+    "USDC_ARB": {
+      "symbol": "USDC",
+      "name": "USD Coin",
+      "chain": "arbitrum",
+      "type": "token",
+      "contract": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
+      "decimals": 6,
+      "billing_enabled": true,
+      "quote_priority": 1,
+      "primary_source": "coingecko",
+      "fallback_source": "static_usd"
+    },
+    "ETH_ETH": {
+      "symbol": "ETH",
+      "name": "Ethereum",
+      "chain": "ethereum",
+      "type": "native",
+      "decimals": 18,
+      "billing_enabled": true,
+      "quote_priority": 2,
+      "primary_source": "coingecko",
+      "fallback_source": "dexscreener"
+    },
+    "ETHO_ETHO": {
+      "symbol": "ETHO",
+      "name": "Etho Protocol",
+      "chain": "etho",
+      "type": "native",
+      "decimals": 18,
+      "billing_enabled": true,
+      "quote_priority": 3,
+      "primary_source": "coingecko",
+      "fallback_source": "local"
+    },
+    "EGAZ_ETICA": {
+      "symbol": "EGAZ",
+      "name": "Etica Gas",
+      "chain": "etica",
+      "type": "native",
+      "decimals": 18,
+      "billing_enabled": true,
+      "quote_priority": 4,
+      "primary_source": "nonkyc",
+      "fallback_source": "local"
+    },
+    "ETI_ETICA": {
+      "symbol": "ETI",
+      "name": "Etica Token",
+      "chain": "etica",
+      "type": "token",
+      "contract": "0x34c61EA91bAcdA647269d4e310A86b875c09946f",
+      "decimals": 18,
+      "billing_enabled": true,
+      "quote_priority": 5,
+      "primary_source": "nonkyc",
+      "fallback_source": "local"
+    }
+  }
+}