Adds an admin-only "Numeros compartilhados entre leads" section to the
settings modal, wired to the Task 4 shared-numbers routes: lists
detected groups, lets an admin liberar (with an inline motivo input)
or bloquear de novo. Updates the two frontend VM-based test files'
default API mocks to answer GET /api/outreach/shared-numbers so
existing settings-modal tests keep passing, and adds a new
interaction test covering the liberar round trip.