P0: stabilize FAT from exact Build #1888 golden baseline

[masarray]

Scope

P0 recovery only. This PR is intentionally based on exact golden ARSAS commit 712e2c557d5da83d2f02b81f3a58905e985d1e50 (Build #1888) and targets baseline/1888-golden so the diff contains only the recovery changes, not later experimental/regression commits.

Fixes

• project authoritative runtime PointUpdated snapshots into FAT Runtime.CurrentValue without UI timers, per-cell subscriptions, or virtualization changes;
• canonicalize FAT Boolean presentation as True / False from first FAT load;
• preserve FAT-first Static DataSet selection as shared Engineering/FAT report-only authority instead of demoting it to Hybrid/live discovery;
• repair stale persisted Static DataSet WorkspaceSelected=false membership in one guarded batch before the FAT V2 view filter is installed, preventing rows from painting and then disappearing;
• preserve the same Static DataSet authority for appended SCL workspaces;
• let report-backed analog values auto-capture Value 1 / Value 2 from authoritative report observations while retaining the 3-sample settling gate for polling analog values;
• remove the normal per-cell manual ✓ Capture surface for analog rows; explicit Recapture remains the operator/audit override;
• initialize Engineering command Interlock + Synchro checks once per command signal, event-driven, without _uiFlushTimer polling;
• add source and functional P0 regression gates that reject the previous post-Measure virtualization hack and keep the golden ARIEC61850 pin unchanged.

Explicitly not changed

• ARIEC61850 pin remains 11ab2304482600c19ba979f4fc9021ddb46b9af9;
• no VirtualizingPanel.SetVirtualizationMode runtime patch;
• no RCB/DataSet/control backend redesign;
• no FAT schema/lifecycle redesign in this P0 (legacy-first-paint cleanup remains a later P1 after bench stability is recovered).

CI / build

Latest head: 7f4841e81d508a39d81c79b04ca0eac747c2f2e0

• Validate IO List Testing #784: PASS
• Validate SV evidence bundles #1009: PASS
• Build ARSAS #1911: PASS
• full solution build: PASS
• application regression tests: PASS
• portable single-EXE publish: PASS
• portable EXE smoke-test: PASS

Bench artifact from Build #1911 is ready for physical relay validation.

Bench acceptance

• SCL opened from FAT + Static DataSet populates Engineering and FAT as one shared workspace; Engineering Play fast-connects/starts Static DataSet acquisition without implicit live discovery;
• FAT rows and Command Signals remain populated;
• physical Open/Closed changes are reflected in FAT Live Value;
• Boolean values stay True/False while scrolling;
• analog Value 1/2 auto-captures without the normal manual Capture button;
• FAT ↔ Engineering/Diagnostics does not freeze;
• golden Command Panel, Value 1/Value 2 evidence, Static DataSet/RCB behavior remain intact.

Keep this PR draft until the exact Build #1911 EXE passes physical bench validation.