Optional guard that runs after authentication but before the MJ shell renders.
If CheckPreShellBlock() returns a component Type, the shell is blocked and
the component is rendered as a full-page overlay. Return null to allow
normal shell rendering.
Consuming libraries provide their implementation via Angular DI:
{ provide: MJ_PRE_SHELL_GUARD, useClass: MyGuardClass }
Optional guard that runs after authentication but before the MJ shell renders. If CheckPreShellBlock() returns a component Type, the shell is blocked and the component is rendered as a full-page overlay. Return null to allow normal shell rendering.
Consuming libraries provide their implementation via Angular DI: { provide: MJ_PRE_SHELL_GUARD, useClass: MyGuardClass }