mgr/dashboard: replace icons.spin with Carbon loading components

mgr/dashboard: replace icons.spin with Carbon loading components

Replace fork-awesome spinner classes with appropriate Carbon loading components:

- cds-inline-loading: for inline spinners (action feedback, status updates)
  * table row actions (executing/removing)
  * upgrade status text/buttons
  * loading panel alerts

- cds-loading size="sm": for section data loading
  * tree view loading (crushmap, multisite-details, cephfs-directories)
  * progress component operations

- cds-loading size="lg": for dashboard/overview loading
  * rgw-overview-dashboard cards
  * multi-cluster overview

Added LoadingModule and InlineLoadingModule imports to:
- block.module.ts
- cephfs.module.ts
- cluster.module.ts
(rgw.module.ts and components.module.ts already had them)

Signed-off-by: Afreen Misbah <afreen@ibm.com>
Assisted-by: Claude
Fixes: https://tracker.ceph.com/issues/76631