deploy: Arbitrum One mainnet (42161) — v4 contracts live

Mi Tanda is live on Arbitrum One, deployed from the v4 audit-hardened code
(commit d17e039). The Tanda implementation's runtime bytecode is an exact
match to the tested build.

- Manager:    0xa88aB3B81D9cA6BB556104B72e73b722D3abE678
- Tanda impl: 0xD55c72B7fF4777D382Bd69b9B27Cc1da799d119d
- Pass / Receipt / Completion NFTs + Genesis collection (#1)
- USDC + MXNB allowlisted; treasury 0x70D3a9aA…; fees 95/2/3
- Chainlink VRF v2.5 (native): sub 39124666…, Manager registered as consumer

Full writeup in deployments/arbitrum-one-mainnet.md; broadcast log under
broadcast/Deploy.s.sol/42161/.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: GeObts