docs: deploy + on-chain verification conventions

AGENTS.md

@@ -31,3 +31,20 @@ Keep this file for knowledge useful to almost every future agent session in this
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+
+## Deploy + verification conventions
+
+- After every prod merge, fast-forward the testnet deployment branch:
+  `git push origin origin/main:testnet`. Both Vercel prods build from their branch.
+- `NEXT_PUBLIC_*` env vars bake at build time — changing one on Vercel does nothing
+  until a redeploy (bit us in the 2026-08-19 Helius key outage).
+- Contract-touching changes can be verified without a funded wallet or foundry:
+  viem `simulateBlocks` (eth_simulateV1) against `https://sepolia.base.org`, using a
+  balance stateOverride + TestUSDC `faucet()` → `approve` → create. Put heavy calls
+  in separate simulated blocks — several multi-million-gas calls in one block hit the
+  shared block-gas ceiling and revert positionally, which looks like a contract limit
+  but isn't.
+- Sablier Lockup Tranched facts (probed on-chain, not docs): tranche cap is exactly
+  500; tranche amounts must sum exactly to the post-broker-fee net deposit or the
+  create reverts — always go through `computeTranches`/`sablierNetDeposit` in
+  `packages/app/src/lib/schedule.ts`.