P1: unify operator workflow and semantic presentation authorities

[masarray]

P1 operator workflow + semantic authority

Stacked on P0 PR #266 exact proven head 7bc76da31f5b90230ec7ec915c71e0e518d31956.

P0 software/CI is green (Build ARSAS #2109 attempt 3), but P0 remains Draft and still requires the physical relay-bench checklist before any golden promotion. This P1 is intentionally independent and must not modify that golden or the pinned ARIEC61850 engine.

P1 scope

• COMTRADE: one FaultRecordRow.IsSelected authority for first download and re-download; downloaded rows remain normally selectable; preserve staged/validated/atomic replacement and per-record failure isolation.
• Semantic naming: move signal display naming into an ARSAS-owned model/projection property so FAT, Engineering presentation, report/CSV and baseline labels share one semantic rule source without modifying ARIEC61850.
• Operator size continuity: keep long IEC references resizable and persist the operator width across FAT window reopen.
• Report/schema sweep: use the same semantic display labels in durable exports while retaining canonical IEC references as technical identity.

Safety constraints

• Base remains P0 branch fix/fat-p0-final-recovery.
• ARIEC61850 stays pinned at 11ab2304482600c19ba979f4fc9021ddb46b9af9.
• Golden remains Build #1888 / ARSAS 712e2c557d5da83d2f02b81f3a58905e985d1e50.
• Keep this PR Draft; do not merge or promote golden from P1.