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/App.tsx

@@ -4,7 +4,7 @@
 // page lands as a content change, not a structural one.
 import { Route, Switch } from 'wouter-preact';
 import { Shell } from './shell/Shell.js';
-import { Panel } from './ui/Panel.js';
+import { Panel } from './ui/panel/Panel.js';
 
 function Home() {
   return (

frontend/packages/swarm-ui/src/swarm-ui.css

@@ -1,5 +1,5 @@
 @import "@hive/shared/base.css";
 @import "./shell/Shell.css";
-@import "./ui/Panel.css";
-@import "./ui/StatusChip.css";
-@import "./ui/Table.css";
+@import "./ui/panel/Panel.css";
+@import "./ui/status-chip/StatusChip.css";
+@import "./ui/table/Table.css";