Remove query-string cache-busting from static assets

Drop ?v=N version pins from all JS imports and HTML <link>/<script> tags.
Cache invalidation is now handled solely by server-side cache-control headers.
Update docs and AGENTS.md accordingly.

webui/static/hoover/components/data.js

@@ -4,11 +4,11 @@
  * Data display components: Badge, StatusDot, Empty, Card.
  */
 
-import { h } from '../vdom.js?v=9';
-import { esc } from '../helpers.js?v=9';
-import { apiFetch, toast } from '../api.js?v=9';
-import { modelFetch } from '../model.js?v=9';
-import { requestUpdate } from '../reactivity.js?v=9';
+import { h } from '../vdom.js';
+import { esc } from '../helpers.js';
+import { apiFetch, toast } from '../api.js';
+import { modelFetch } from '../model.js';
+import { requestUpdate } from '../reactivity.js';
 
 const _actionPending = new Map();
 const _confirmPending = new Map();