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/render.js

@@ -5,12 +5,12 @@
  * batched re-render loop integration with reactivity.js.
  */
 
-import { requestUpdate, setCommitFn } from './reactivity.js?v=9';
+import { requestUpdate, setCommitFn } from './reactivity.js';
 import {
     _vnodeDom, createDom, getDom, patchNode, sweepDom,
     setMountFn, setUnmountFn,
-} from './vdom.js?v=9';
-import { mountComponent, unmountComponent } from './component.js?v=10';
+} from './vdom.js';
+import { mountComponent, unmountComponent } from './component.js';
 
 /** Container → previous root vnodes */
 export const _renderSlots = new Map();