Factor out remaining references to deprecated ethereum-api.xyz/blockchain-api.xyz

[bkrem]

Description

• ethereum-api.xyz and blockchain-api.xyz are unmaintained and will be deprecated
• We need to factor out any remaining old references to these APIs in our examples and replace functionality to preserve feature parity; e.g. ethereum-api.xyz to be replaced by the more mature rpc.walletconnect.com

Steps

• Factor out dependence on ethereum-api.xyz in current examples
• Factor out dependence on blockchain-api.xyz in current examples
• Remove stale chat examples (including Vercel projects and DNS subdomains)
• Clean up blockchain-api.xyz references in the SE-SDK sample: https://github.com/WalletConnect/se-sdk/blob/bfc633e3387fa20e3f76316d37fe8960573c2a8c/examples/dapp/src/chains/eip155.ts#L10: refactor: replace blockchain-api.xyz references with assets WalletConnect/se-sdk#23
• Clean up remaining usage of caip-api (https://github.com/pedrouid/caip-api/tree/beta) pkg which internally relies on blockchain-api.xyz
• Archive stale v1 example repos (e.g. https://github.com/WalletConnect/walletconnect-example-dapp) and redirect DNS to equivalent v2 examples (e.g. https://example.walletconnect.org/)