0766 — CLI commands mirror client verbs

Context

CLI reads mixed current values, history, and status under get. Passing —limit changed an alert read into history, while schedule messages were a flag and key messages a command. Schedule also differed from Scheduler.

Decision

• Use scheduler for the client’s Scheduler handle; get, status, and messages invoke their corresponding methods separately.
• Metric and alert reads use latest and history; only history accepts —limit.
• Key compaction-head names CompactionHead; messages keeps Messages.
• System register names System().Register and applies default system config.
• Metric —series-limit bounds attribute sets; —limit bounds entries.
• Keep collection plurals: messages, migrate streams, migrate versions, and the Prometheus —metrics-address endpoint.
• Remove the former spellings without aliases. Update help, examples, and error recovery commands together.

Consequences

Pre-v1 scripts must update command paths and metric —series. Scheduler get no longer includes consumer_groups or messages in its JSON document; status and messages each return their own array. System register returns registered rather than a hard-coded migration version. Removed flags and command paths are rejected, making stale invocations visible instead of changing their read.