feat(auth)!: ScadaBridge canonical roles + SoD collapse (Audit→Administrator, AuditReadOnly→Viewer) + config-DB migration (Task 1.7)

Standardize role string VALUES on the canonical vocabulary
(Administrator/Designer/Deployer/Viewer; Operator/Engineer unused here):
  Admin        -> Administrator
  Design       -> Designer
  Deployment   -> Deployer
  Audit        -> Administrator   (COLLAPSE; accepted privilege escalation)
  AuditReadOnly-> Viewer          (COLLAPSE; keeps audit-read, no export)

SoD: OperationalAuditRoles = { Administrator, Viewer },
     AuditExportRoles      = { Administrator }
so Viewer reads the audit log + nav but cannot bulk-export, while
Administrator does both + holds the full admin surface (the documented,
accepted auditor/admin SoD collapse).

Atomic move across every enforcement site:
- Roles constants; AuthorizationPolicies (RequireClaim values + SoD arrays +
  honest XML-doc); RoleMapper Deployer check.
- ManagementActor.GetRequiredRole switch + the hard-coded site-scope
  admin-bypass (now Roles.Administrator at all 6 sites). Site-scoping logic
  is otherwise unchanged.
- DebugStreamHub Administrator/Deployer gates (Deployer kept case-sensitive).
- CentralUI BrowseService/BindingTester Designer guards; LdapMappingForm
  dropdown now offers canonical values (incl. Viewer).
- Config-DB seed (LdapGroupMappings Id 1-4) + EF migration CanonicalizeRoles:
  Id-keyed UpdateData for seed rows + idempotent raw catch-all UPDATEs for
  operator-added rows. Down is lossy on the collapse (documented in-file).
  No pending model changes.

Tests reworked to the collapsed model across Security/CentralUI/
ManagementService/ConfigurationDatabase/Integration suites, incl. explicit
Viewer-reads-not-exports and former-Audit-now-Administrator-escalation cases.

CHANGELOG: BREAKING security note documenting the canonicalization + SoD
collapse.

tests/ZB.MOM.WW.ScadaBridge.CentralUI.Tests/Audit/AuditExportEndpointsTests.cs

@@ -81,7 +81,7 @@ public class AuditExportEndpointsTests
                     // Use the real production policy wiring so the endpoint's
                     // updated AuditExport gate (#23 M7-T15 Bundle G) is what
                     // the tests exercise. The fake principal carries the
-                    // "Admin" role, which AuditExportRoles permits.
+                    // "Administrator" role, which AuditExportRoles permits.
                     services.AddScadaBridgeAuthorization();
                     services.AddSingleton(repo);
                     services.AddScoped<IAuditLogExportService, AuditLogExportService>();
@@ -288,7 +288,7 @@ public class AuditExportEndpointsTests
             var claims = new[]
             {
                 new Claim(ClaimTypes.Name, "test-admin"),
-                new Claim(JwtTokenService.RoleClaimType, "Admin"),
+                new Claim(JwtTokenService.RoleClaimType, "Administrator"),
             };
             var identity = new ClaimsIdentity(claims, SchemeName);
             var principal = new ClaimsPrincipal(identity);