Add Chainlink and Spectra Finance to ecosystem.md

La modifica va in skills/standards/ecosystem.md: aggiungi la voce Chainlink sotto ## Oracles, prima di #### Band Protocol, e la voce Spectra Finance sotto ### Yield & Vaults, dopo #### DeFindex. L'issue fornisce il testo proposto e gli indirizzi e dichiara che i link sono stati verificati. Conferma ogni link e ogni indirizzo con la rispettiva fonte prima dell'inserimento, quindi verifica che il Markdown renderizzato corrisponda alle voci circostanti. È completato quando entrambe le voci sono al loro posto con link funzionanti e la struttura delle sezioni è invariata.

Two projects launched on Stellar mainnet. skills/standards/ecosystem.md does not list them. Agents that use the skill do not know about them.

Summary

Proposed text: Chainlink

#### Chainlink
Data Feeds and Data Streams live on Stellar (October 2026).
- **Docs**: https://docs.chain.link/data-feeds/stellar
- **Feed IDs**: https://docs.chain.link/data-feeds/price-feeds/addresses?network=stellar (select Stellar)
- **Proxy (mainnet)**: `CDQBHEUGLDHMSUHG4IH33RJBUTMNCZOT4JIAQR4WZFRDZW6DR6S32ZLZ`
- **Proxy (testnet)**: `CBUF6IADAWPWIDWRTHJNINKXHG2UTIQ6TU2F2HRAXWAI7OT3KJPKK6O4`
- **Interface**: not SEP-40. One proxy serves every feed; select a feed by its 32-byte `data_id`. `latest_round(data_id, decimals)` and `get_round(data_id, round_id, decimals)` return `Round { round_id, answer: I256, timestamp }`. Answers are stored at 18 decimals; pass `18` unless Chainlink approved a lower precision. Interface source: https://github.com/smartcontractkit/chainlink-stellar
- **Example**: BTC/USD `data_id` `01a0b4d920000332000000000000000000000000000000000000000000000000` (same on testnet and mainnet)
- **Data Streams**: pull model; verify signed reports on-chain with the Chainlink Verifier contract. Needs an allowlisted account. Guide: https://docs.chain.link/data-streams/tutorials/stellar-onchain-report-verification

Proposed text: Spectra Finance

#### Spectra Finance
Fixed-rate yield markets: splits a yield-bearing asset into a Principal Token (PT) and a Yield Token (YT). Live on Stellar mainnet; Stellar markets accept XLM and USDC and swap them into the market asset first.
- **Use Case**: Lock a fixed rate (buy PT), trade future yield (YT)
- **App**: https://app.spectra.finance/fixed-rate?network=stellar
- **Docs**: https://docs.spectra.finance/docs/stellar
- **Developer docs**: https://dev.spectra.finance/docs/stellar (Core v2 integration, router and limit orders, IBT wrappers, PT bridge, oracle)
- **Mainnet contracts**: https://dev.spectra.finance/docs/technical-reference/deployed-contracts#stellar-mainnet (Registry, PT Factory, Router, Limit Order Engine, PT Bridge, PT Oracle Factory)
- **Features**: Core v2 on Soroban, PT/YT limit orders, Blend wrapper (Blend positions as vault shares), PT bridge to EVM, deterministic zero-coupon-bond PT oracle
- **Caveat**: PT market deployment is permissionless. Registry membership is discovery data, not an allowlist.

Why the details matter for agents

• The Chainlink proxy is not SEP-40. An agent that assumes lastprice() will write broken code.
• One proxy serves all feeds. The agent must use a data_id, not a per-feed contract address.
• Answers use 18 decimals, and the decimals argument is required.
• Data Streams needs an allowlisted account. The agent should say so before it suggests Data Streams.
• Spectra PT markets are permissionless. A market in the Registry is not an approved market.

Verification

• Chainlink proxy addresses come from Chainlink docs.
• I called latest_round with the BTC/USD data_id on both proxies (--send=no). Both returned live rounds with description = BTC/USD.
• Spectra contract list comes from Spectra developer docs. I confirmed the Registry contract on mainnet.
• All links return 200.

Left out

• Chainlink mainnet feed list. The Chainlink page renders it with JS. The entry links to it.
• Data Streams mainnet Verifier address. Chainlink docs show only the testnet one.
• Specific Spectra markets. The only Stellar market in the app matures on 2026-10-16.

Sources

• Chainlink launch post
• Chainlink Data Feeds on Stellar
• Chainlink Data Streams on Stellar
• Spectra post on X
• Spectra on Stellar
• Build with Spectra on Stellar

Related

• stellar/stellar-docs#2918
• stellar/ecosystem-resources#25