add contract adddresses table (#805)

Author: hughescoin

docs/base-chain/quickstart/builder-codes.mdx

@@ -275,6 +275,14 @@ Builder codes work with the [Base-Solana bridge](/base-chain/quickstart/base-sol
 Mainnet support for Builder Codes is not open to all builders yet. If you are interested in getting access, please contact the team on [discord](https://discord.gg/buildonbase).
 </Tip>
 
+## Contract Addresses
+
+| Contract | Base Mainnet | Base Sepolia |
+| -------- | ------------ | ------------ |
+| `BRIDGE_CAMPAIGN_ADDRESS` | `0x539A97cc4724d5b2740DB98Bc71445448eFC1Bde` | `0xE2AD1C34382410C30d826B019A0B3700F5c4e6c9` |
+| `FLYWHEEL_ADDRESS` | `0x00000F14AD09382841DB481403D1775ADeE1179F` | `0x00000F14AD09382841DB481403D1775ADeE1179F` |
+| `MULTICALL_ADDRESS` | `0xcA11bde05977b3631167028862bE2a173976CA11` | `0xcA11bde05977b3631167028862bE2a173976CA11` |
+
 ## Give feedback!
 
 <Note>