Fix all baseline code-review findings across the six shared libraries

Resolves the 35 findings from the 2026-06-01 baseline (commit 26ba1c7),
test-first for every behavioral change. +51 tests (331 -> 382 passing, 0 failed).

- Telemetry-001 (HIGH): RedactionEnricher now honours property removal, so a
  redactor that drops a key actually scrubs the secret from the event.
- Auth: LDAP validator ValidateOnStart; API-key verify no longer fails on a
  best-effort MarkUsed write or a corrupt scopes column (fail-closed); LDAP cert
  validation hook; KeyPrefix persistence aligned; README algorithm corrected.
- Health: Akka checks return Degraded (not throw) when the cluster isn't up yet;
  GrpcDependencyHealthCheck catch-all; null 'description' rendered; composite
  endpoint builder; XML docs shipped.
- Audit: CompositeAuditWriter no longer re-throws OperationCanceledException;
  TruncatingAuditRedactor over-redact scrubs Target + safe negative max; options
  record; XML docs shipped.
- Configuration: TryAddEnumerable idempotent registration; consistent port
  quoting; strict invariant port parsing; XML docs + README packaged.
- Theme: mobile toggle is now CSS-only (no Bootstrap JS); token/CSS hygiene;
  XML docs on the public parameter surface.

Shared-contract/spec docs updated where the code was the source of truth
(observability service.instance.id, MapZbMetrics, redactor reach). All changes
additive/back-compatible at v0.1.0. code-reviews bookkeeping follows separately.

ZB.MOM.WW.Telemetry/README.md

@@ -55,6 +55,14 @@ Trace↔log correlation is automatic: `TraceContextEnricher` reads `Activity.Cur
 log event and attaches `trace_id` and `span_id`, so log events produced inside a traced request
 carry the same span identity as the trace backend.
 
+**Redaction reach.** A registered `ILogRedactor` may **remove** or **replace** any top-level
+property, and `RedactionEnricher` honours both (a removed key is dropped from the event). The seam
+sees the unwrapped value of scalar properties only — a destructured `{@Object}` property is exposed
+as its raw Serilog `StructureValue` wrapper, so a redactor can replace/remove the whole structured
+property but **cannot** mask a field nested inside it. To protect a sensitive field of a logged
+object, log it as its own scalar property (do not destructure it) or remove the whole property by
+key. See the `ILogRedactor` XML doc for the full contract.
+
 ---
 
 ## Exporter options
@@ -113,9 +121,9 @@ backend):
 
 | Assembly | Tests |
 |---|---|
-| `ZB.MOM.WW.Telemetry.Tests` | 7 |
-| `ZB.MOM.WW.Telemetry.Serilog.Tests` | 12 |
-| **Total** | **19** |
+| `ZB.MOM.WW.Telemetry.Tests` | 12 |
+| `ZB.MOM.WW.Telemetry.Serilog.Tests` | 17 |
+| **Total** | **29** |
 
 ---