swarm-ui: one subdirectory per ui/ component

Per mara's PR review request: Panel/StatusChip/Table each move into
their own subdir (ui/panel/, ui/status-chip/, ui/table/) colocating
the component with its stylesheet, matching shell/ (Shell.tsx +
Shell.css already lived this way). Import paths in App.tsx and
swarm-ui.css updated to match; no behavior change.

npm run build + typecheck both clean.

frontend/packages/swarm-ui/src/ui/Table.tsx

@@ -1,43 +0,0 @@
-// <Table> — a generic column-defined table, the shape the hive roster
-// (name / domain / status chip, one row per hive) needs. Columns own
-// their own cell rendering rather than this component knowing about
-// any particular row shape, so it stays reusable for the swarm-wide
-// agent roster later without a rewrite.
-import type { ComponentChildren } from 'preact';
-
-export interface TableColumn<T> {
-  key: string;
-  header: string;
-  render: (row: T) => ComponentChildren;
-}
-
-export function Table<T>({
-  columns,
-  rows,
-  rowKey,
-}: {
-  columns: TableColumn<T>[];
-  rows: T[];
-  rowKey: (row: T) => string;
-}) {
-  return (
-    <table class="ui-table">
-      <thead>
-        <tr>
-          {columns.map((c) => (
-            <th key={c.key}>{c.header}</th>
-          ))}
-        </tr>
-      </thead>
-      <tbody>
-        {rows.map((row) => (
-          <tr key={rowKey(row)}>
-            {columns.map((c) => (
-              <td key={c.key}>{c.render(row)}</td>
-            ))}
-          </tr>
-        ))}
-      </tbody>
-    </table>
-  );
-}