Phase 6.1 Stream E (data layer) — DriverInstanceResilienceStatus entity + DriverResilienceStatusTracker + EF migration

Ships the data + runtime layer of Stream E. The SignalR hub and Blazor /hosts
page refresh (E.2-E.3) are follow-up work paired with the visual-compliance
review per Phase 6.4 patterns — documented as a deferred follow-up below.

Configuration:
- New entity DriverInstanceResilienceStatus with:
  DriverInstanceId, HostName (composite PK),
  LastCircuitBreakerOpenUtc, ConsecutiveFailures, CurrentBulkheadDepth,
  LastRecycleUtc, BaselineFootprintBytes, CurrentFootprintBytes,
  LastSampledUtc.
- Separate from DriverHostStatus (per-host connectivity view) so a Running
  host that has tripped its breaker or is nearing its memory ceiling shows up
  distinctly on Admin /hosts. Admin page left-joins both for display.
- OtOpcUaConfigDbContext + Fluent-API config + IX_DriverResilience_LastSampled
  index for the stale-sample filter query.
- EF migration: 20260419124034_AddDriverInstanceResilienceStatus.

Core.Resilience:
- DriverResilienceStatusTracker — process-singleton in-memory tracker keyed on
  (DriverInstanceId, HostName). CapabilityInvoker + MemoryTracking +
  MemoryRecycle callers record failure/success/breaker-open/recycle/footprint
  events; a HostedService (Stream E.2 follow-up) samples this tracker every
  5 s and persists to the DB. Pure in-memory keeps tests fast + the core
  free of EF/SQL dependencies.

Tests:
- DriverResilienceStatusTrackerTests (9 new, all pass): tryget-before-write
  returns null; failures accumulate; success resets; breaker/recycle/footprint
  fields populate; per-host isolation; snapshot returns all pairs; concurrent
  writes don't lose counts.
- SchemaComplianceTests: expected-tables list updated to include the new
  DriverInstanceResilienceStatus table.

Full solution dotnet test: 1042 passing (baseline 906, +136 for Phase 6.1 so
far across Streams A/B/C/D/E.1). Pre-existing Client.CLI Subscribe flake
unchanged.

Deferred to follow-up PR (E.2/E.3):
- ResilienceStatusPublisher HostedService that samples DriverResilienceStatusTracker
  every 5 s + upserts DriverInstanceResilienceStatus rows.
- Admin FleetStatusHub SignalR hub pushing LastCircuitBreakerOpenUtc /
  CurrentBulkheadDepth / LastRecycleUtc on change.
- Admin /hosts Blazor column additions (red badge when
  ConsecutiveFailures > breakerThreshold / 2). Visual-compliance reviewer
  signoff alongside Phase 6.4 admin-ui patterns.

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

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/DriverInstanceResilienceStatus.cs

@@ -0,0 +1,44 @@
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>
+///     Runtime resilience counters the CapabilityInvoker + MemoryTracking + MemoryRecycle
+///     surfaces for each <c>(DriverInstanceId, HostName)</c> pair. Separate from
+///     <see cref="DriverHostStatus"/> (which owns per-host <i>connectivity</i> state) so a
+///     host that's Running but has tripped its breaker or is approaching its memory ceiling
+///     shows up distinctly on Admin <c>/hosts</c>.
+/// </summary>
+/// <remarks>
+///     Per <c>docs/v2/implementation/phase-6-1-resilience-and-observability.md</c> §Stream E.1.
+///     The Admin UI left-joins this table on DriverHostStatus for display; rows are written
+///     by the runtime via a HostedService that samples the tracker at a configurable
+///     interval (default 5 s) — writes are non-critical, a missed sample is tolerated.
+/// </remarks>
+public sealed class DriverInstanceResilienceStatus
+{
+    public required string DriverInstanceId { get; set; }
+    public required string HostName { get; set; }
+
+    /// <summary>Most recent time the circuit breaker for this (instance, host) opened; null if never.</summary>
+    public DateTime? LastCircuitBreakerOpenUtc { get; set; }
+
+    /// <summary>Rolling count of consecutive Polly pipeline failures for this (instance, host).</summary>
+    public int ConsecutiveFailures { get; set; }
+
+    /// <summary>Current Polly bulkhead depth (in-flight calls) for this (instance, host).</summary>
+    public int CurrentBulkheadDepth { get; set; }
+
+    /// <summary>Most recent process recycle time (Tier C only; null for in-process tiers).</summary>
+    public DateTime? LastRecycleUtc { get; set; }
+
+    /// <summary>
+    ///     Post-init memory baseline captured by <c>MemoryTracking</c> (median of first
+    ///     BaselineWindow samples). Zero while still warming up.
+    /// </summary>
+    public long BaselineFootprintBytes { get; set; }
+
+    /// <summary>Most recent footprint sample the tracker saw (steady-state read).</summary>
+    public long CurrentFootprintBytes { get; set; }
+
+    /// <summary>Row last-write timestamp — advances on every sampling tick.</summary>
+    public DateTime LastSampledUtc { get; set; }
+}