Phase 7: serve the vet sample from the template tools and docs

- build.py: _TEMPLATE_COMPONENTS rewritten around the vet sample (53 kinds —
  per-resource slices, jobs, worked appointment_reminder family, tests);
  seed tokens dropped from the manifest ('sample: vet' instead)
- registry.py: get_app_component(kind) no longer renames item/example seeds;
  prompts and tool docs updated to 'copy a slice and adapt'
- templates/README.md, 01_build_recipe, 40_ui_admin, wiki/03 updated off the
  old seed scheme; repo inventory/config now exclude vet (docs move under
  standards; react/vet itself is deleted in a later phase)
- regenerated MCP bundle, vendored templates, and site output

standards/mcp/templates/app/interfaces/system/routes.py

@@ -8,6 +8,6 @@ async def health() -> dict:
     """Liveness probe — public, unauthenticated.
 
     Returns:
-        dict: ``{"status": "ok", "service": "app-template"}``.
+        dict: ``{"status": "ok", "service": "vet-server"}``.
     """
-    return {"status": "ok", "service": "app-template"}
+    return {"status": "ok", "service": "vet-server"}