Add API to support saving local only resources

[ndegwamartin]

IMPORTANT: All PRs must be linked to an issue (except for extremely trivial and straightforward changes).

Fixes #2123

Description
Clear and concise code change description.
See #2123

Alternative(s) considered
Have you considered any alternatives? And if so, why have you chosen the approach in this PR?
See #2123

Type
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Feature

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• I have discussed my proposed solution with code owners in the linked issue(s) and we have agreed upon the general approach.
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[aditya-07]

IMO, adding a default value to FhirEngine.create to specify whether the resources are meant to be local only is a better design choice.

Additionally, we would want all the updates to the resource to be local only as well. Therefore, we should mark the resource as local only in the db itself.

[aditya-07]

Suggested change

	suspend fun create(vararg resource: Resource): List<String>
	/**
	* Creates one or more remote FHIR [resource]s in the local storage without flagging as local
	* changes.
	*/
	suspend fun createRemote(vararg resource: Resource)
	/**
	* Creates one or more FHIR [resource]s in the local storage.
	*
	* @param isLocalOnly - Setting the value to [true] instructs engine that the resource and its subsequent updates should never be synced to the server.
	* @return the logical IDs of the newly created resources.
	*/
	suspend fun create(vararg resource: Resource, isLocalOnly: Boolean = false): List<String>

The default value can be provided in the interface i.e FhirEngine.kt and the FhirEngineImpl.kt would be called with that value if no value is provided by the caller.

[aditya-07]

Suggested change

	override suspend fun createRemote(vararg resource: Resource) {
	return database.insertRemote(*resource)
	}

insertRemote would just add the resource in the db without creating a LocalChange counterintuitively marking the change as local only.

[aditya-07]

Looking at the test, createRemote is doing what it is supposed to do. But, the name createRemote is counterintuitive and suggests that the resource has something to do with the remote server. A more intutive name could have be createLocal ?

[ndegwamartin]

@aditya-07 could you have a second look to see if this is what you had in mind?

[ndegwamartin]

@jingtang10 you had a concern with the updates for the related resources processed by the implementation here, could you share that here or on the ticket #2123 ?

[ndegwamartin]

This is blocked by/Superseded by this discussion - #2625

[jingtang10]

This is blocked by/Superseded by this discussion - #2625

why is this blocked by custom resources?