task: Replace the remaining live Alfajores references — six pages still instruct readers to use a retired testnet

Follow-up from #2277, which cleared partner addresses but left the retired-testnet references behind.

`AGENTS.md` § *Code examples* says: **testnet is Celo Sepolia, chain ID 11142220. Alfajores (44787) is retired — do not reference it.** 20 `.mdx` files still mention Alfajores. Most are legitimate history and are **not** in scope. Six carry it as a *live instruction* — a reader following them lands on a dead network.

### In scope — live instructions pointing at a retired testnet

| Page | Evidence |
|---|---|
| `tooling/libraries-sdks/portal/index.mdx` | `eip155:44787` is the worked example in five code blocks (lines 172, 231, 245, 259, 273), plus the Alfajores RPC at line 172. This is the only page outside archives that still hands a reader chain ID 44787 to copy. |
| `tooling/contracts/uniswap-contracts.mdx` | A whole **"Alfajores Address"** column (line 33 header, rows from line 35) linking to `alfajores.celoscan.io`. Presented as current reference, not history. |
| `tooling/libraries-sdks/contractkit/odis.mdx` | Lines 65–66 and 73–74 list Alfajores and Alfajores-Staging ODIS endpoints and public keys in the current-service tables. |
| `tooling/libraries-sdks/contractkit/setup.mdx` | Line 51: "In this example will use `alfajores`" — the page's only network example. |
| `tooling/libraries-sdks/contractkit/migrating-to-viem.mdx` | Line 21 `https://alfajores-forno.celo-testnet.org`; line 194 "same on mainnet and alfajores"; line 234 `// ALFAJORES ADDRESS`. |
| `contribute-to-celo/release-process/attestation-service.mdx` | Lines 56, 113, 122, 124 — an Alfajores release runbook for a service that is itself retired. **OPEN:** fix the network names or delete the page; needs an owner's call, not a find-and-replace. |

### Explicitly out of scope — Alfajores is correct here

Dated changelog and archive entries (`home/history.mdx`, `build-on-celo/index.mdx:54`, `operate/notices/archive/*`, `operate/specification/upgrades/{ice-cream,isthmus}.mdx`), the sentences that name Alfajores *as the thing being replaced* (`build-on-celo/network-overview.mdx`, `tooling/testnets/celo-sepolia/index.mdx`, `home/bridged-tokens/native-ETH-bridging.mdx`, `build-on-celo/build-with-ai/self-agent-id.mdx:30`), the L1 transaction-type history in `home/protocol/transactions/transaction-types.mdx`, and the `` argument in the L1→L2 runbook `operate/operators/migrate-node.mdx`.

Also out of scope: the 14 `alfajores` strings in `docs.json` — those are redirect **sources** and must keep working.

### Definition of done

- [ ] The five mechanical pages use Celo Sepolia (`11142220`, `https://forno.celo-sepolia.celo-testnet.org`, `celo-sepolia.blockscout.com` / `celoscan` equivalent) wherever a reader is meant to act.
- [ ] Uniswap and ODIS: the Sepolia values are **verified on-chain / against the live service** before they land, per `AGENTS.md` — not translated from the Alfajores row. Where no Sepolia deployment exists, drop the column rather than invent one.
- [ ] `attestation-service.mdx` decided: renamed networks or deleted with a redirect.
- [ ] `npx mintlify broken-links` green.

### How we'd know it's fixed

`grep -rniE 'alfajores|44787' --include='*.mdx' .` returns only the out-of-scope pages listed above.

### Non-goals

Redirect sources in `docs.json`; rewriting the history and archive pages; re-verifying the Celo Sepolia values already on other pages.

Read AGENTS.md § Code examples, then run the listed grep and inspect the five mechanical pages: portal/index.mdx, uniswap-contracts.mdx, odis.mdx, setup.mdx, and migrating-to-viem.mdx. Verify Sepolia values against the live service before changing them; ask the owner to decide whether attestation-service.mdx is renamed or deleted. Run npx mintlify broken-links and confirm only the documented out-of-scope references remain.

Written by the indexing model from the issue text.