Phase 6.1 Stream A follow-up — DriverInstance.ResilienceConfig JSON column + parser + OtOpcUaServer wire-in

Closes the Phase 6.1 Stream A.2 "per-instance overrides bound from
DriverInstance.ResilienceConfig JSON column" work flagged as a follow-up
when Stream A.1 shipped in PR #78. Every driver can now override its Polly
pipeline policy per instance instead of inheriting pure tier defaults.

Configuration:
- DriverInstance entity gains a nullable `ResilienceConfig` string column
  (nvarchar(max)) + SQL check constraint `CK_DriverInstance_ResilienceConfig_IsJson`
  that enforces ISJSON when not null. Null = use tier defaults (decision
  #143 / unchanged from pre-Phase-6.1).
- EF migration `20260419161008_AddDriverInstanceResilienceConfig`.
- SchemaComplianceTests expected-constraint list gains the new CK name.

Core.Resilience.DriverResilienceOptionsParser:
- Pure-function parser. ParseOrDefaults(tier, json, out diag) returns the
  effective DriverResilienceOptions — tier defaults with per-capability /
  bulkhead overrides layered on top when the JSON payload supplies them.
  Partial policies (e.g. Read { retryCount: 10 }) fill missing fields from
  the tier default for that capability.
- Malformed JSON falls back to pure tier defaults + surfaces a human-readable
  diagnostic via the out parameter. Callers log the diag but don't fail
  startup — a misconfigured ResilienceConfig must not brick a working
  driver.
- Property names + capability keys are case-insensitive; unrecognised
  capability names are logged-and-skipped; unrecognised shape-level keys
  are ignored so future shapes land without a migration.

Server wire-in:
- OtOpcUaServer gains two optional ctor params: `tierLookup` (driverType →
  DriverTier) + `resilienceConfigLookup` (driverInstanceId → JSON string).
  CreateMasterNodeManager now resolves tier + JSON for each driver, parses
  via DriverResilienceOptionsParser, logs the diagnostic if any, and
  constructs CapabilityInvoker with the merged options instead of pure
  Tier A defaults.
- OpcUaApplicationHost threads both lookups through. Default null keeps
  existing tests constructing without either Func unchanged (falls back
  to Tier A + tier defaults exactly as before).

Tests (13 new DriverResilienceOptionsParserTests):
- null / whitespace / empty-object JSON returns pure tier defaults.
- Malformed JSON falls back + surfaces diagnostic.
- Read override merged into tier defaults; other capabilities untouched.
- Partial policy fills missing fields from tier default.
- Bulkhead overrides honored.
- Unknown capability skipped + surfaced in diagnostic.
- Property names + capability keys are case-insensitive.
- Every tier × every capability × empty-JSON round-trips tier defaults
  exactly (theory).

Full solution dotnet test: 1215 passing (was 1202, +13). Pre-existing
Client.CLI Subscribe flake unchanged.

Production wiring (Program.cs) example:
  Func<string, DriverTier> tierLookup = type => type switch
  {
      "Galaxy" => DriverTier.C,
      "Modbus" or "S7" => DriverTier.B,
      "OpcUaClient" => DriverTier.A,
      _ => DriverTier.A,
  };
  Func<string, string?> cfgLookup = id =>
      db.DriverInstances.AsNoTracking().FirstOrDefault(x => x.DriverInstanceId == id)?.ResilienceConfig;
  var host = new OpcUaApplicationHost(..., tierLookup: tierLookup, resilienceConfigLookup: cfgLookup);

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

src/ZB.MOM.WW.OtOpcUa.Configuration/Migrations/OtOpcUaConfigDbContextModelSnapshot.cs

@@ -413,6 +413,9 @@ namespace ZB.MOM.WW.OtOpcUa.Configuration.Migrations
                         .HasMaxLength(64)
                         .HasColumnType("nvarchar(64)");
 
+                    b.Property<string>("ResilienceConfig")
+                        .HasColumnType("nvarchar(max)");
+
                     b.HasKey("DriverInstanceRowId");
 
                     b.HasIndex("ClusterId");
@@ -431,6 +434,8 @@ namespace ZB.MOM.WW.OtOpcUa.Configuration.Migrations
                     b.ToTable("DriverInstance", null, t =>
                         {
                             t.HasCheckConstraint("CK_DriverInstance_DriverConfig_IsJson", "ISJSON(DriverConfig) = 1");
+
+                            t.HasCheckConstraint("CK_DriverInstance_ResilienceConfig_IsJson", "ResilienceConfig IS NULL OR ISJSON(ResilienceConfig) = 1");
                         });
                 });