P0: finalize FAT field-bench recovery authorities

[masarray]

P0 final field-bench recovery

Stacked on the latest proven PR #265 head 8d83f3ec435c5bcb1891f54eff48030ab3e5cf2a.

This PR is intentionally incremental. It must not redesign ARIEC61850, the generic interoperable SCL exporter, or the existing Engineering-first SCL/runtime ownership established in PR #265.

P0 scope

• lock FAT TEST checkbox authority to operator/persistence; no software auto-untick;
• preserve immediate FAT LIVE VALUE and harden LIVE-before-evidence publication ordering;
• make RCB inclusion genuinely independent multi-select, including row click, Shift-range, and keyboard operation;
• preserve native/static DataSets while excluding ARSAS runtime/dynamic acquisition DataSets from SCL export;
• retain Engineering-owned OFFLINE/smart reconnect and close/re-import evidence continuity;
• add behavioral regressions for field-critical interaction state instead of relying only on source-string assertions.

Safety gates

• ARIEC61850 remains pinned at 11ab2304482600c19ba979f4fc9021ddb46b9af9 and must not be changed.
• Golden remains Build #1888 / ARSAS 712e2c557d5da83d2f02b81f3a58905e985d1e50.
• Keep this PR Draft.
• Do not merge or call the candidate golden until exact-head Build + IO + SV gates pass and the physical relay bench passes Start/Continue/Stop, LIVE-before-evidence, multi-RCB SCL export, COMTRADE re-download selection, unplug/reconnect, and close/re-import/Continue FAT.