Add ISAC registry search controls

docs/DESIGN_SYSTEM.md

@@ -633,6 +633,20 @@ never silently describe only the visible page. On narrow screens, retain
 previous, next, current page, and page-size controls before optional page
 numbers.
 
+Registries with a meaningful name, title, or agent-identity column place the
+shared server-side search inside this pagination rail. Submission resets the
+page number while preserving the selected KPI filter and row-count preset;
+page navigation preserves the query. Provide an explicit clear action whenever
+a query is active. Search applies to the complete filtered registry before
+pagination, including visible pending proposals, and never only to the current
+page. Specialized oversight and history searches may remain in their richer
+filter consoles when they search evidence beyond a single identity column.
+
+At intermediate widths the search spans the pagination rail above its range
+and navigation controls. At mobile widths all groups stack, the input retains a
+usable width, and search, clear, previous, and next remain explicit keyboard
+and touch targets.
+
 ### Registry metric filters
 
 The KPI row above an ISAC registry is an operational filter surface, not passive