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.Auth/src/ZB.MOM.WW.Auth.ApiKeys/Admin/ApiKeyAdminCommands.cs

@@ -101,7 +101,10 @@ public sealed class ApiKeyAdminCommands
 
         var record = new ApiKeyRecord(
             KeyId: keyId,
-            KeyPrefix: $"{_options.TokenPrefix}_{keyId}",
+            // KeyPrefix is the bare token prefix (e.g. "mxgw"), NOT prefix_keyId — the key id is
+            // already its own column. Embedding it here produced a self-referential value that
+            // confused admin tooling and disagreed with the read/test paths (see Auth-005).
+            KeyPrefix: _options.TokenPrefix,
             SecretHash: secretHash,
             DisplayName: displayName,
             Scopes: scopes,