List virtual networks in the active scope

Returns the paginated collection of virtual networks (VNets) visible in the active tenant/subscription/project scope, exactly as consumed by the Networks page on route load. Each row carries the stable identifiers, status, CIDR, MTU, shared/external flags and embedded subnets/ports the table needs. This single endpoint also serves the search/filter/sort/paginate behavior (canonical action network.network.search_filter_sort): free-text q matches name or CIDR, the status filter maps the "Active"/"Building" quick chips, and shared=true maps the "Shared" chip; sort/order cover the sortable Name and Created columns. Validation: scopeId must resolve to a tenant/subscription/project the caller can read, else 403 FORBIDDEN; malformed pagination/filter values (unknown status, non-boolean shared, page<1) map to 422 VALIDATION_FAILED. Async & state: Synchronous read; no state change. Rows in BUILD will transition to ACTIVE/ERROR via resource.updated SSE frames the client may merge. Errors: 401 when unauthenticated; 403 when the caller lacks reader access to the scope; 422 on malformed query parameters; 500 on backend read-model failure. Idempotency/Concurrency: Safe, cacheable; no idempotency key required.