docs: scheduled prompts are swarm-level; the hive page is a read-only list

Drops docs/tools/scheduling.md and every description of hive-level
schedule creation, the worker, the removed MCP tools, the scheduling tool
group and the removed endpoints/events, pointing at docs/swarm/schedules.md.

hive-c0re/README.md

@@ -1,7 +1,7 @@
 # hive-c0re
 
 The unprivileged host daemon (runs as `hive-core`). Owns the sqlite
-broker, the approval/reminder/schedule queues, the generic job-DAG
+broker, the approval/reminder queues, the generic job-DAG
 queue, container lifecycle, gateway vhost wiring, forge/matrix config
 reconciliation, per-container stats, and the axum operator dashboard.
 Largest crate in the workspace — bin-only, no separate lib.
@@ -32,7 +32,7 @@ to track it:
 - **`lifecycle/`** — `nixos-container` lifecycle + per-agent config
   flake generation.
 - **`stores/`** — sqlite-backed stores (broker, queues, audit, power).
-- **`workers/`** — background sweeps (crash watch, scheduled prompts,
+- **`workers/`** — background sweeps (crash watch,
   autoupdate, knowledge sync).
 - **`agent_config/`** — per-agent registries (tool groups,
   capabilities, resource limits, topology).