Fix live dataset and cross-domain report planning

[masarray]

What changed

• carry requested DataSet-directory results in the typed MMS discovery result and consume them in live-model/profile builders
• preserve DataSet member order and expose member counts in discovery diagnostics
• allow verified-free dynamic RCB pools to host temporary DataSets whose members are in other Logical Devices
• add deterministic regressions for discovery handoff and cross-domain dynamic planning

Root cause

ARSAS received only DataSet names from DiscoverAsync, so its live model had zero DataSet members. Hybrid dynamic planning also filtered residual signals to the RCB's MMS domain, which made Siemens ADD-domain URCB pools unusable for measurement domains even though MMS named-variable-list members can be cross-domain.

Validation

• dotnet test ARIEC61850.sln -c Release — 573 passed
• scripts/verify-source-clean.cmd — passed
• read-only IEDScout probe: 2 DataSets / 58 members, static BRCB+URCB full coverage, and a cross-domain DynamicUrcb plan using ADD/LLN0.RP.A_URCB01

Evidence boundary

The IEDScout run was read-only planning and value-read evidence. No RCB/DataSet activation write was issued by the audit probe.