feat(events): enablement, per-run caps and mayInvoke (Phase 6)

Two new tables — event_action_settings (the deployment switchboard) and
event_run_budget (what a run has spent and the most it may) — plus verified_at
and verified_by on event_versions. The whole authorisation decision moves behind
one function, events/authorize.js: role, enablement, cap, and the shard's own
switch named as the layer core deliberately does not duplicate.

Three routes, none moved: GET/PUT /admin/events/actions (admin in both
directions) and POST /admin/events/:id/verify (admin, editor — a dry run
dispatches nothing).

Four decisions, settled by the org lead 2026-09-03:

- The default-off line falls between inspect and change, not between notify and
  inspect. Read literally, §K shipped core.wait disabled. The same line is the
  role floor.
- The tightest cap wins where two actions spend one dimension, pinned into the
  run at creation with the action it came from.
- A refusal follows the step's on_failure and takes health to degraded — its own
  status and its own log kind, because a refusal is not an outage.
- The verify gate is enforced for scheduled starts only: a human pressing Start
  now is the review the gate exists to require.

Derived and flagged for review: a dry run fails rather than warns on a disabled
action or an over-cap plan, and the unattended path does not re-check the
starter's role.

+111 tests (1921/1847/73/1 — the one failure pre-existing and environmental),
including a 403 walk over the real router and two concurrent spends against one
cap on a real MariaDB. The live walk found two defects, both fixed here: the run
console route dropped the budget it was handed, and the role refusal used a
plural verb over a one-item list.

Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01T6t8mrAWhZU5vnyYgZTMtL

server/src/model/events/eventDefinitions.db.js

@@ -16,9 +16,16 @@ const hydrate = (row) =>
 // `current_version` is joined rather than stored: the list screen shows "v3" and
 // the column that would hold it is a denormalisation of a row this query already
 // has to reach for the publish date anyway.
+//
+// `current_version_verified_at` rides along for the same reason and answers the
+// same kind of question (Phase 6). A `ready` definition whose version has never
+// been dry-run will not start on its schedule (§K), and the one place that fact
+// is worth saying is the screen its author is already looking at -- the
+// alternative is finding out on the Friday it did not run.
 const SELECT_LIST = `
   SELECT d.*, s.name AS series_name, s.slug AS series_slug,
-         v.version AS current_version
+         v.version AS current_version,
+         v.verified_at AS current_version_verified_at
     FROM event_definitions d
     LEFT JOIN event_series   s ON s.id = d.series_id
     LEFT JOIN event_versions v ON v.id = d.current_version_id