feat: P-1222 added graph getter for OmniAccount in client-sdk

[higherordertech]

Context

As title.

The implementation is replicated from the heima test code:

heima/tee-worker/identity/ts-tests/integration-tests/common/utils/native-request-helpers.ts

Lines 219 to 225 in cdc652d

	export const getOmniAccount = async (parachainApi: ApiPromise, identity: CorePrimitivesIdentity): Promise<string> => {
	const omniAccount = await parachainApi.rpc.state.call('OmniAccountApi_omni_account', identity.toHex());
	return encodeAddress(omniAccount.toHex());
	};
	export const getOmniAccountNonce = async (

Labels

Please apply following PR-related labels when appropriate:

• C0-breaking: if your change could break the existing client, e.g. API change, critical logic change
• C1-noteworthy: if your change is non-breaking, but is still worth noticing for the client, e.g. reference code improvement

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Testing Evidences

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[linear]

P-1222 add missing getters for omni account

[kziemianek]

Is accountStore.unwrap() the only call that can throw an error ?
If not it might ignore it (for example query error) and return null so user will think that account doesn't exists

[silva-fj]

This getter should probably get the data from the worker (TrustedGetter) as private members are encrypted. But since we are rewriting the id worker in the omni-executor maybe it would be better to wait a bit for this.