chore(deps): move every ZB.MOM.WW pin to the newest published version

Auth 0.1.5 -> 0.2.0, Health 0.2.0 -> 0.3.0, Secrets/.Abstractions/.Ui
0.6.1 -> 0.6.2. Theme, GalaxyRepository, Audit, Configuration, Telemetry
and Telemetry.Serilog were already at the newest version on the feed.

Checked against the shared-lib source rather than the version numbers,
because these packages are versioned as a family and a bump is not by
itself evidence that the package changed:

- Auth 0.2.0 is the only one carrying content for us: LDAP backup-DC
  failover (FallbackServers, endpoint walk with sticky preference,
  boot-time entry validation). Purely additive; the default is empty,
  which leaves single-endpoint behaviour unchanged.
- Health 0.3.0 carries a breaking change, but every line of it is in
  ZB.MOM.WW.Health.Akka, which we do not reference. No commit touched
  the core ZB.MOM.WW.Health package between 0.2.0 and 0.3.0.
- Secrets 0.6.2 is a message-only change: one validator string literal
  gains mounted-volume guidance. SecretsStorePathRules is untouched.

The four non-csproj files are not a separate feature. Configuration/
LdapOptions is a deliberate shadow of the shared type and carries an
explicit warning to mirror any new upstream field, because AddZbLdapAuth
binds the whole MxGateway:Ldap section onto the shared options. So
FallbackServers is live on our config surface the moment the package
lands, and without the mirror an operator could configure a backup DC
that works but is invisible on the dashboard's Settings page. The
Settings row renders "none" when empty, since that is the answer someone
who believes a backup DC is configured actually needs.

Entry syntax is deliberately NOT re-validated here: the shared validator
already fails the boot on a malformed entry and owns the (internal)
parser, so a second copy would drift. Note both validators skip entirely
when Ldap:Enabled is false.

Verified the binder is non-strict (ErrorOnUnknownConfiguration is unused
anywhere in the tree), so the upgrade could not break startup on a
newly-recognised key either way.

Build 0 warnings / 0 errors; gateway suite 892/892, unchanged. The live
LDAP tests are opt-in and were not run, so the failover path itself is
covered only by the shared library's own tests.

docs/GatewayConfiguration.md

@@ -254,6 +254,7 @@ dev/test GLAuth posture (`glauth.md`), not a production posture.
 | `MxGateway:Ldap:UserNameAttribute` | `cn` | LDAP attribute holding the login user name. |
 | `MxGateway:Ldap:DisplayNameAttribute` | `cn` | LDAP attribute holding the display name. |
 | `MxGateway:Ldap:GroupAttribute` | `memberOf` | LDAP attribute enumerating group membership (mapped to dashboard roles via `MxGateway:Dashboard:GroupToRole`). |
+| `MxGateway:Ldap:FallbackServers` | *(empty)* | Ordered backup LDAP endpoints tried when the primary fails with a system-side error (connect/TLS, service-account bind, or search) — **not** when a user's credentials are simply wrong. Each entry is `host` (adopting `Port`) or `host:port`. Empty leaves single-endpoint behaviour exactly as before. Endpoint preference is sticky: the last endpoint that answered keeps being used until it fails. The `Transport` / `AllowInsecure` policy applies to every endpoint — a fallback is not a way to downgrade TLS. Entries are parsed at startup and a malformed one fails the boot, so a typo'd backup DC cannot lie dormant until the outage it exists to survive. Requires ZB.MOM.WW.Auth 0.2.0+. |
 
 When LDAP is enabled, `Server`, `SearchBase`, `ServiceAccountDn`,
 `ServiceAccountPassword`, and the attribute names must be non-blank, and `Port`