Phase 2 PR 7 — wire IHistoryProvider.ReadProcessedAsync end-to-end. PR 5 ported HistorianDataSource.ReadAggregateAsync into Galaxy.Host but left it internal — GalaxyProxyDriver.ReadProcessedAsync still threw NotSupportedException, so OPC UA clients issuing HistoryReadProcessed requests against the v2 topology got rejected at the driver boundary. This PR closes that gap by adding two new Shared.Contracts messages (HistoryReadProcessedRequest/Response, MessageKind 0x62/0x63), routing them through GalaxyFrameHandler, implementing HistoryReadProcessedAsync on all three IGalaxyBackend implementations (Stub/DbBacked return the canonical "pending" Success=false, MxAccessGalaxyBackend delegates to _historian.ReadAggregateAsync), mapping HistorianAggregateSample → GalaxyDataValue at the IPC boundary (null bucket Value → BadNoData 0x800E0000u, otherwise Good 0u), and flipping GalaxyProxyDriver.ReadProcessedAsync from the NotSupported throw to a real IPC call with OPC UA HistoryAggregateType enum mapped to Wonderware AnalogSummary column name on the Proxy side (Average → "Average", Minimum → "Minimum", Maximum → "Maximum", Count → "ValueCount", Total → NotSupported since there's no direct SDK column for sum). Decision #13 IPC data-shape stays intact — HistoryReadProcessedResponse carries GalaxyDataValue[] with the same MessagePack value + OPC UA StatusCode + timestamps shape as the other history responses, so the Proxy's existing ToSnapshot helper handles the conversion without a new code path. MxAccessGalaxyBackend.HistoryReadProcessedAsync guards: null historian → "Historian disabled" (symmetric with HistoryReadAsync); IntervalMs <= 0 → "HistoryReadProcessed requires IntervalMs > 0" (prevents division-by-zero inside the SDK's Resolution parameter); exception during SDK call → Success=false Values=[] with the message so the Proxy surfaces it as InvalidOperationException with a clean error chain. Tests — HistoryReadProcessedTests (new, 4 cases): disabled-error when historian null, rejects zero interval, maps Good sample with Value=12.34 and the Proxy-supplied AggregateColumn + IntervalMs flow unchanged through to the fake IHistorianDataSource, maps null Value bucket to 0x800E0000u BadNoData with null ValueBytes. AggregateColumnMappingTests (new, 5 cases in Proxy.Tests): theory covers all 4 supported HistoryAggregateType enum values → correct column string, and asserts Total throws NotSupportedException with a message that steers callers to Average/Minimum/Maximum/Count (the SDK's AnalogSummaryQueryResult doesn't expose a sum column — the closest is Average × ValueCount which is the responsibility of a caller-side aggregation rather than an extra IPC round-trip). InternalsVisibleTo added to Galaxy.Proxy csproj so Proxy.Tests can reach the internal MapAggregateToColumn static. Builds — Galaxy.Host (net48 x86) + Galaxy.Proxy (net10) both 0 errors, full solution 201 warnings (pre-existing) / 0 errors. Test counts — Host.Tests Unit suite: 28 pass (4 new processed + 9 PR5 historian + 15 pre-existing); Proxy.Tests Unit suite: 14 pass (5 new column-mapping + 9 pre-existing). Deferred to a later PR — ReadAtTime + ReadEvents + Health IPC surfaces (HistorianDataSource has them ported in PR 5 but they need additional contract messages and would push this PR past a comfortable review size); the alarm subsystem wire-up (OnAlarmEvent raising from MxAccessGalaxyBackend) which overlaps the ReadEventsAsync IPC work since both pull from HistorianAccess.CreateEventQuery on the SDK side; the Proxy-side quality-byte refinement where HistorianDataSource's per-sample raw quality byte gets decoded through the existing QualityMapper instead of the category-only mapping in ToWire(HistorianSample) — doesn't change correctness today since Good/Uncertain/Bad categories are all the Admin UI and OPC UA clients surface, but richer OPC DA status codes (BadNotConnected, UncertainSubNormal, etc.) are available on the wire and the Proxy could promote them before handing DataValueSnapshot to ISubscribable consumers. This PR branches off phase-2-pr5-historian because it directly extends the Historian IPC surface added there; if PR 5 merges first PR 7 fast-forwards, otherwise it needs a rebase after PR 5 lands.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/ZB.MOM.WW.OtOpcUa.Driver.Galaxy.Host/Ipc/GalaxyFrameHandler.cs

@@ -80,6 +80,13 @@ public sealed class GalaxyFrameHandler(IGalaxyBackend backend, ILogger logger) :
                     await writer.WriteAsync(MessageKind.HistoryReadResponse, resp, ct);
                     return;
                 }
+                case MessageKind.HistoryReadProcessedRequest:
+                {
+                    var resp = await backend.HistoryReadProcessedAsync(
+                        Deserialize<HistoryReadProcessedRequest>(body), ct);
+                    await writer.WriteAsync(MessageKind.HistoryReadProcessedResponse, resp, ct);
+                    return;
+                }
                 case MessageKind.RecycleHostRequest:
                 {
                     var resp = await backend.RecycleAsync(Deserialize<RecycleHostRequest>(body), ct);