E2E test script — Galaxy (MXAccess) driver: read / write / subscribe / alarms / history

Seven-stage e2e script covering every Galaxy-specific capability surface:
IReadable + IWritable + ISubscribable + IAlarmSource + IHistoryProvider.
Unlike the other drivers there is no per-protocol CLI — Galaxy's proxy
lives in-process with the server + talks to OtOpcUaGalaxyHost over a
named pipe (MXAccess COM is 32-bit-only), so every stage runs through
`otopcua-cli` against the published OPC UA address space.

## Stages

1. Probe                   — otopcua-cli read on the source NodeId
2. Source read             — capture value for downstream comparison
3. Virtual-tag bridge      — Phase 7 VirtualTag (source × 2) through
                             CachedTagUpstreamSource
4. Subscribe-sees-change   — data-change events propagate
5. Reverse bridge          — opc-ua write → Galaxy; soft-passes if the
                             attribute's Galaxy-side ACL forbids writes
                             (`BadUserAccessDenied` / `BadNotWritable`)
6. Alarm fires             — scripted-alarm Condition fires with Active
                             state when source crosses threshold
7. History read            — historyread returns samples from the Aveva
                             Historian → IHistoryProvider path

## Two new helpers in _common.ps1

- `Test-AlarmFiresOnThreshold` — start `otopcua-cli alarms --refresh`
  in the background on a Condition NodeId, drive the source change,
  assert captured stdout contains `ALARM` + `Active`. Uses the same
  Start-Process + temp-file pattern as `Test-SubscribeSeesChange` since
  the alarms command runs until Ctrl+C (no built-in --duration).
- `Test-HistoryHasSamples` — call `otopcua-cli historyread` over a
  configurable lookback window, parse `N values returned.` marker, fail
  if below MinSamples. Works for driver-sourced, virtual, or scripted-
  alarm historized nodes.

## Wiring

- `test-all.ps1` picks up the optional `galaxy` sidecar section and
  runs the script with the configured NodeIds + wait windows.
- `e2e-config.sample.json` adds a `galaxy` section seeded with the
  Phase 7 defaults (`p7-smoke-tag-source` / `-vt-derived` /
  `-al-overtemp`) — matches `scripts/smoke/seed-phase-7-smoke.sql`.
- `scripts/e2e/README.md` expected-matrix gains a Galaxy row.

## Prereqs

- OtOpcUaGalaxyHost running (NSSM-wrapped) with the Galaxy + MXAccess
  runtime available
- `seed-phase-7-smoke.sql` applied with a live Galaxy attribute
  substituted into `dbo.Tag.TagConfig`
- OtOpcUa server running against the `p7-smoke` cluster
- Non-elevated shell (Galaxy.Host pipe ACL denies Admins)

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

scripts/e2e/e2e-config.sample.json

@@ -49,6 +49,17 @@
         "bridgeNodeId": "ns=2;s=TwinCAT/MAIN_iCounter"
     },
 
+    "galaxy": {
+        "$comment": "Galaxy (MXAccess) driver. Has no per-driver CLI — all stages go through otopcua-cli against the published NodeIds. Seven stages: probe / source read / virtual-tag bridge / subscribe-sees-change / reverse write / alarm fires / history read. Requires OtOpcUaGalaxyHost running + seed-phase-7-smoke.sql applied with a real Galaxy attribute substituted into dbo.Tag.TagConfig.",
+        "sourceNodeId": "ns=2;s=p7-smoke-tag-source",
+        "virtualNodeId": "ns=2;s=p7-smoke-vt-derived",
+        "alarmNodeId": "ns=2;s=p7-smoke-al-overtemp",
+        "alarmTriggerValue": "75",
+        "changeWaitSec": 10,
+        "alarmWaitSec": 10,
+        "historyLookbackSec": 3600
+    },
+
     "phase7": {
         "$comment": "Virtual tags + scripted alarms. The VirtualNodeId must resolve to a server-side virtual tag whose script reads the modbus InputNodeId and writes VT = input * 2. The AlarmNodeId is the ConditionId of a scripted alarm that fires when VT > 100.",
         "modbusEndpoint": "127.0.0.1:5502",