WIP: address PR #475 review feedback

frontend/scripts/help-assets.ts

@@ -159,10 +159,9 @@ export const helpAssets = (): Plugin => {
       configResolved (config) {
 	state.root = path.resolve (config.root, 'help')
       },
-      async buildStart () {
-	state.data = generateHelpAssets (state.root)
-	const generated = await data ()
-	generated.files.forEach (file => this.addWatchFile (file))
+      buildStart () {
+	state.data = undefined
+	this.addWatchFile (state.root)
       },
       resolveId (id) {
 	return id.startsWith (prefix) ? `\0${ id }` : null
@@ -170,7 +169,9 @@ export const helpAssets = (): Plugin => {
       async load (id) {
 	if (!(id.startsWith (`\0${ prefix }`)))
 	  return null
-	const source = (await data ()).modules.get (id.slice (1))
+	const generated = await data ()
+	generated.files.forEach (file => this.addWatchFile (file))
+	const source = generated.modules.get (id.slice (1))
 	if (source == null)
 	  throw new Error (`Unknown Help asset: ${ id.slice (1) }`)
 	return source