P0: repair FAT relay-bench runtime latency

[masarray]

FAT relay-bench recovery — field round-3 candidate / physical relay re-bench required

Golden reference remains Build #1888 / ARSAS commit 712e2c557d5da83d2f02b81f3a58905e985d1e50. ARIEC61850 remains immutable at pin 11ab2304482600c19ba979f4fc9021ddb46b9af9; no ARIEC source, patch, package pin, or lock change is part of this recovery.

Previous relay candidate 725b96fae257cf65aec4d8282b3016ffb98887f3 failed the physical gate: COMTRADE showed a duplicated synthetic tick, the production RCB action still surfaced RCB Export Filter — Legacy SAS, and Sync could start unchecked.

Current exact candidate head: 96cc945a62f481689ed26b85eb404f47ca4e3327.

Field round-3 corrections

• COMTRADE selection: removed the synthetic ✓ content/glyph entirely. The real WPF checkbox owns checkbox clicks; the separate class handler now handles row-body clicks only. Downloaded records still use _redownloadSelections, first downloads use IsSelected, and staged safe overwrite remains unchanged. One click = one state transition = one normal checkbox tick.
• RCB multi-select production route: the IED-card RCB action is intercepted at the Button.ClickEvent class-handler level before the legacy XAML instance handler can run. The realized button also removes IedEditRcb_Click and installs IedEditRcbMulti_Click. Identification no longer depends on Tag != null; the operator-facing route must open RCB Export — Generic IEC 61850 SCL. The multi window retains independent RcbExportRow.IsSelected checkboxes and exports every selected RCB.
• Interlock/Sync default: command-default registration moved from an unreliable static-field initializer to a [ModuleInitializer] class-handler registration. Every command signal is initialized Interlock=true and Sync=true; those defaults are protected while ctlModel hydrates, written once more when ctlModel resolves, then operator changes are respected.

Existing relay-bench protections retained

• FAT semantic DO/DA/phase-aware names and IEC Reference resizing;
• report-snapshot LIVE projection before Value1/Value2 evidence;
• FAT membership never silently mutates TEST;
• OFFLINE/reconnect and shared Engineering/FAT command backend;
• multi-RCB SCL keeps selected native RCBs/native DataSets only and does not create ARSAS runtime acquisition DataSets;
• PR remains Draft and must not merge until physical relay validation passes.

Exact-head CI gate — GREEN on 96cc945a

• ✅ Build ARSAS #2125 — source/invariant checks, solution build, full regression, portable publish, portable smoke test, artifact upload.
• ✅ Validate IO List Testing #995.
• ✅ Validate SV evidence bundles #1221.
• ✅ Full regression suite: 808 / 808 passed, 0 failed.
• ✅ ARIEC61850 immutable lock/API verification passed at 11ab2304482600c19ba979f4fc9021ddb46b9af9.

Portable candidate:

• Artifact: ARSAS-win-x64-portable-single-exe (10022385436)
• Artifact ZIP SHA-256: 0b053d82616a36e4ad3e5e9e5891f9c415c66dbde3d5de5b0c5e586db4303ef5
• Executable: ARSAS-1.6.33-win-x64-portable.exe
• EXE SHA-256: 6d2903cf51b6c9c401b1d67ac5ef76b0cde70c548eab11798a0fd69019b64455

Physical relay re-bench gate for this exact build

1. COMTRADE row must show exactly one normal checkbox tick; checkbox click and row click each toggle exactly once; multiple downloaded records remain selectable.
2. IED-card RCB action must open RCB Export — Generic IEC 61850 SCL, never Legacy SAS; select 2+ arbitrary RCBs and verify all remain checked through export.
3. Engineering and FAT command rows must initially show Interlock checked + Sync checked. After ctlModel is resolved, a deliberate operator uncheck must remain respected.

Keep this PR Draft. Do not merge until exact head 96cc945a passes the physical relay re-bench.

[masarray]

Relay-bench P0 Gate 1 is green at db81148d0f429f6df27c0eea577b6ea8e07164f6.

Passed:

• Build ARSAS #1929
• Validate IO List Testing #802
• Validate SV evidence bundles #1027

Gate 1 repairs report-backed analog Value 1/Value 2 latency and removes per-event physical disk barriers while keeping final journal durability/seal verification. Proceeding to the next isolated gate: fast FAT attach to an already-live shared Engineering Static DataSet/RCB acquisition session. PR remains draft and must not merge before physical relay acceptance.

[masarray]

P0 LIVE VALUE + Command Panel gate completed on c1063c79b9fbc47341542f70695df8be50cd4ccc.

• LIVE VALUE now prefers the shared Engineering device.Points process image/report-backed state; non-forced MMS inspection remains only for missing values.
• FAT Command Panel retains row instances for normal value/result/busy updates. LIVE VALUE/result/model/enablement are bound in-place; structural synchronization happens only when the command collection changes, and confirmation/semantic transitions replace only the action cell.
• Regression coverage now explicitly rejects RebuildFatCommandRows and forced FAT RefreshControlValuesAsync(..., force: true).
• CI corrections during the gate were limited to completing required IoTestPointPlan fixture fields and updating the old source-text assertion to the new null-safe/shared-collection implementation.

Full CI green:

• Build ARSAS #1945 ✅ (full regressions + portable publish/smoke)
• Validate IO List Testing #818 ✅
• Validate SV evidence bundles #1043 ✅

ARIEC61850 source was not modified; immutable pin remains 11ab2304482600c19ba979f4fc9021ddb46b9af9.

PR intentionally remains draft. Physical relay-bench Start/capture/Recapture/command/LIVE VALUE acceptance is still required before merge.

[masarray]

P0 locked-scope verification — LIVE VALUE + stable Command Panel

Re-verified the current PR head c1063c79b9fbc47341542f70695df8be50cd4ccc against the locked P0 scope.

• LIVE VALUE is genuinely live, not attach-time-only: the FAT bridge seeds values from the shared Engineering device.Points process image, rebuilds the control-feedback index, and the existing runtime point-update path projects matching report-backed point updates into SignalDefinition.ControlCurrentValue through _controlFeedbackIndex.
• No normal full-row rebuild: Command Panel retains row view instances; ControlCurrentValue, ControlLastResult, busy/enabled state, CDC and control-model text are binding-driven. Structural collection changes synchronize rows; confirmation/semantic transitions replace only the action cell.
• No forced FAT MMS refresh regression: fallback refresh remains force: false; shared process-image projection is reapplied afterward.
• ARIEC61850 remains immutable for this P0: pinned engine revision 11ab2304482600c19ba979f4fc9021ddb46b9af9; no engine-source change is needed.

Full CI on this exact head is green:

• Build ARSAS #1945 — success
• Validate IO List Testing #818 — success
• Validate SV evidence bundles #1043 — success

No additional code churn is warranted for this locked P0. PR should remain draft until physical-relay acceptance; P1 remains out of scope until that gate is stable.

[masarray]

Repair status update — current head 478909f

Implemented on this branch:

• ✅ Rolling Value 1 / Value 2 — a completed evidence pair now advances on each new real process condition; repeated identical values do not churn evidence. Example 0 → 1000 → 0 ends at Value1=1000, Value2=0.
• ✅ Start FAT / preparation UI hot-loop removal — the preparation progress layer no longer traverses the full WPF visual tree every 50 ms at Render priority. It now runs at Background priority / 100 ms, returns immediately while idle, and updates cached progress bars only while preparation is active. A regression test locks this behavior.
• ✅ COMTRADE FAT report cleanup — removed the Download column plus OPTIONAL / not a FAT gate wording. FileDirectory evidence now presents the remote file identity, relay-modified timestamp, and evidence source directly. Regression assertions now reject the removed wording.

Previously locked on the same PR:

• ✅ already-live Engineering fast attach for FAT Start
• ✅ event-driven report-backed first/changed value capture
• ✅ no per-event physical disk barrier in evidence journal
• ✅ command-panel routine updates without full-row rebuild
• ✅ LIVE VALUE projected from the shared Engineering process image, with no forced FAT MMS refresh

Still open / not yet claimed fixed:

• ⏳ close-path latency while active evidence journals are synchronously sealed/verified
• ⏳ command Open/Close latency on a physical relay
• ⏳ multi-RCB selection/export workflow
• ⏳ normalized already-downloaded COMTRADE re-download/overwrite selection
• ⏳ one-row FAT header + report sign-off block

Current full CI has been triggered for head 478909f; Build ARSAS, Validate IO List Testing, and Validate SV evidence bundles are still running at the time of this update. ARIEC61850 remains unchanged at immutable pin 11ab2304482600c19ba979f4fc9021ddb46b9af9.