CAIP-2 standard support

[lordshashank]

Request to support CAIP-2, in synapse which enables cross chain and smart contract account compatible providers to be used.
Basically I am trying embedded wallet support for eastore.xyz, and facing this issue

errors.ts:17 Uncaught (in promise) Error: NetworkUtils getFilecoinNetworkType failed: Failed to detect network: invalid BigNumberish string: Cannot convert eip155:314159 to a BigInt (argument="value", value="eip155:314159", code=INVALID_ARGUMENT, version=6.15.0)
    at createError (errors.ts:17:18)
    at getFilecoinNetworkType (network.ts:40:22)
    at async WarmStorageService.create (service.ts:142:25)
    at async Synapse.create (synapse.ts:131:32)
    at async SynapseProvider.useCallback[initializeSynapse] (SynapseContext.tsx:35:29)

which is because the

synapse-sdk/packages/synapse-sdk/src/utils/network.ts

Line 22 in bdb6bbb

const network = await provider.getNetwork()

call fails in case of embedded wallet as the chain id is expected to be in bigint for but instead it is in caip-2 form as "eip155:314159" which leads to parsing failure. This was leading to failiure in Synapse.create as it was not able to detect network.
This would enable people to do gas sponsorships, enable smart accounts, etc through synapse.

[lordshashank]

on some fast initial check, something like this could resolve the issue above

        let chainId;

        try {
            // 1. Try a low-level RPC call first to get the raw value
            // This bypasses ethers' internal validation which crashes on "eip155:..."
            const rawChainId = await (provider as any).send('eth_chainId', []);

            // 2. Handle CAIP-2 format (e.g., "eip155:314159") or Hex (e.g., "0x4cb1f")
            const chainIdStr = String(rawChainId);
            const cleanId = chainIdStr.includes(':')
                ? chainIdStr.split(':')[1]
                : chainIdStr;

            chainId = Number(cleanId);
        } catch (rpcError) {
            // Fallback to standard getNetwork if the manual call fails for some reason
            const network = await provider.getNetwork();
            chainId = Number(network.chainId);
        }

but yeah more research and e2e testing needed to make this work.

[BigLep]

I've set the milestone for post-GA.