docs: fix and fill gaps in the kubectl-ate CLI reference

[botengyao]

Follow-up to #561, doc-only — happy to open an issue if preferred.

#561 fixed the kubectl ate logs examples that omitted the required -a/--atespace. Two more documented commands have the same problem:

• cmd/kubectl-ate/README.md, the --trace example: kubectl ate get actor my-counter-1 --trace
• demos/parking/README.md: kubectl ate get actors

Both fail with --atespace is required when getting actors / specify --atespace <name> to list one atespace, or -A/--all-atespaces for all.

While in the CLI README, three gaps that a first-time reader hits:

• The get actor STATUS column lists 4 states; the API defines 8. Added STATUS_PAUSING, STATUS_PAUSED, STATUS_CRASHED, STATUS_DELETING (all reachable — the control plane sets each of them today).
• pause actor was undocumented. Added it alongside suspend, with a note on the distinction that matters in practice: suspend uploads the snapshot so the actor can resume anywhere, pause keeps it on the node VM and biases the next resume back to that node.
• top was undocumented, even though the get workers section already pointed at "the same flags as top workers". Added a section with the flags and the output columns, plus a note that it needs metrics-server.

Plus a typo in hack/update/proto-fmt.sh ("wince" → "since").

• Tests pass
• Appropriate changes to documentation are included in the PR