feat(events): the step editor reworked, and event templates (MODULE_API 1.13.0)

Rust PLAN_REDESIGNS §2 (U-3-U-6, F11; D192, D334), core half. Game-agnostic:
Module-uo's steps get the new controls and nothing else.

Contract (MODULE_API 1.12.0 -> 1.13.0, four optional additions):
- api.registerEventTemplates([{ id, label, description, inputs, build }]):
  inputs are params (<= 8); core checks them, calls build() (10 s), validates
  the result as a spec and answers an unsaved draft.
  POST /admin/events/catalog/templates/:templateId (admin, editor).
- a param's duration: 'minutes' (int/float only); core.lease's minutes has it.
- a lease's example for its value.
- an option row's note (<= 300 chars), shown under the chosen field.

Editor:
- no type tags or bare asterisks; a required field says so in words once a
  save has been tried with it empty (and the save stops before the round trip).
- boolean: toggle when required, [Not set] [Yes] [No] when optional (D334).
- a choice of two or three is a row of buttons (lease values, small sources).
- core.lease drawn as the chosen lease: picked by label; value by the lease's
  type, range, values and example; target picker over target.source (F11);
  minutes with the lease's longest hold.
- a timed step keeps its run open: a phase with no advance rule gets
  after: <longest hold> when a timed step is added; a sentence under any phase
  whose run can end sooner (U-6).
- Start asks "Publish and start" or "Start version N" when the working copy is
  ahead of the published version (draftAhead on GET/PUT/publish; U-5).
- New event can start from a module's template.
- core's own examples name no game (§0.9).

Swagger, routes.manifest/guards and engagement-triggers.json regenerated.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E14m6SuuY6i1vASFeGDBeY

client/src/api/client.js

@@ -518,6 +518,10 @@ export const api = {
       const qs = q ? `?${new URLSearchParams({ q }).toString()}` : ''
       return req(`/admin/events/catalog/options/${encodeURIComponent(sourceId)}${qs}`)
     },
+    // MODULE_API 1.13.0. Fill an event template in; the answer is a draft the
+    // editor opens, and nothing is saved until the author saves it.
+    buildEventTemplate: (templateId, inputs) =>
+      req(`/admin/events/catalog/templates/${encodeURIComponent(templateId)}`, { method: 'POST', body: { inputs } }),
     // Phase 6. The dry run is admin+editor: it dispatches nothing, and the author
     // who wrote the definition is who should be able to price it against the caps
     // before asking an admin to publish it. A report with findings comes back 200