Nodes can join or reload snapshots after roles and tables
already exist, so the cache cannot rely only on
incremental notifications.
Bulk-load all known roles and tables into the rule cache
on Raft state reload and snapshot transfer. Detect
incremental role creates and drops in reload_modules() by
comparing the loaded roles against the auth cache, and
forward the changes to every shard.
Each shard rebuilds the fnmatch cache locally from its own
rules to avoid cross-shard races when rules are updated
concurrently with entity sync.
Refs SCYLLADB-1430
c810bb48f4