[kasrakhosravi]

• Adds a short section on eRPC (open-source, self-hosted RPC proxy) to the eSpace RPC Providers page.
• eRPC is not a provider; it fails over between the providers listed on the page and caches responses.
• Tested: the snippet's config returns eth_chainId 0x406 for 5/5 calls, also with the first upstream down.

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