adds envio to graph indexers

docs/develop/graphs-indexers/index.md

@@ -17,3 +17,4 @@ of decentralized applications and make it easier for users to access and analyze
 | **Covalent** | Provides a Unified API for accessing data from over 100 blockchain networks. Indexing service for all EVM transactions on Evmos                                                                  | `evm`          | <ul><li>Get an [API Key](https://www.covalenthq.com/platform/#/auth/register/)</li><li>[Docs](https://www.covalenthq.com/docs/networks/evmos/)</li><li>Cost: Free to use with 100,000 credits to use their API endpoints</li></ul>                                                                                                                                                                                                    |
 | **Numia**    | Indexes both EVM and Cosmos transactions on Evmos. Also indexes other chains on the Cosmos ecosystem. The service runs on Google BigQuery and requires users to sign up for their own accounts. | `cosmos` `evm` | <ul><li>[Get started with GCP instruction](https://docs.numia.xyz/using-numia/getting-started-with-gcp)</li><li>[Pulling Numia Data Image](https://docs.numia.xyz/using-numia/querying-numia-datasets)</li><li>[Evmos chain](https://docs.numia.xyz/using-numia/chains/evmos)</li><li>[Google Cloud](https://cloud.google.com/) provides free trial with ample credits ($300) to run many queries for at least a few months</li></ul> |
 | **[SubQuery](https://subquery.network/)** | A fast, reliable, and decentralised indexer empowering developers to build customised APIs for their web3 projects. Supporting over 100+ networks, get started with our SDK, managed service & decentralised network. | `cosmos` + `evm` | <ul><li>[Quick start](https://academy.subquery.network/quickstart/quickstart.html)</li><li>[Managed Services](https://managedservice.subquery.network/)</li><li>[Decentralised Network](https://subquery.network/network)</li></ul> |
+| **[Envio](https://envio.dev/)** | Envio is a full-featured data indexing solution that provides application developers with a seamless and efficient way to index and aggregate real-time and historical blockchain data for any EVM. Designed to optimize the user experience, Envio offers automatic code generation, flexible language support, multi-chain data aggregation, and a reliable cost-effective hosted service. | `evm` | <ul><li>[Quickstart](https://docs.envio.dev/docs/quickstart)</li><li>[Hosted Service](https://docs.envio.dev/docs/hosted-service)</li><li>[Contract Import](https://docs.envio.dev/docs/contract-import)</li></ul> |