fix: endpoint device & group members typing

[Nerivec]

• endpoint.getDevice() could potentially be undefined => log error/stack trace
• group._members required array conversion for use in some places => use array as base instead (with check on add)

@Koenkk I'm a little worried that this didn't trip coverage, smells like hidden coverage issues, particularly for Group.
The members getter for Group is a little awkward. It also results in lots of chained calls because more often than not, Z2M will chain the result with some other filters on top. And typing is crappy too, because getDevice shouldn't be undefined for resulting items since that's the whole purpose of the getter. See any easy way to change this?

[Koenkk]

Shouldn't we just throw an exception when device === undefined? I'm not sure when exactly this can happen.

[Nerivec]

There are places where undefined was being checked against the return value, even though the type didn't allow it, so, I don't think we can just throw.

zigbee-herdsman/src/controller/model/group.ts

Line 31 in c9e3fd1

return Array.from(this._members).filter((e) => e.getDevice());

[Koenkk]

And how can the device get undefined?

[Nerivec]

Should be only if deleted

zigbee-herdsman/src/controller/model/device.ts

Lines 634 to 638 in c9e3fd1

	public static byIeeeAddr(ieeeAddr: string, includeDeleted: boolean = false): Device | undefined {
	Device.loadFromDatabaseIfNecessary();
	return includeDeleted ? (Device.deletedDevices.get(ieeeAddr) ?? Device.devices.get(ieeeAddr)) : Device.devices.get(ieeeAddr);
	}