web interfaces: don't include version number in html, only return it after authentication

second round for issue #322

webadmin/admin.ts

@@ -2,12 +2,13 @@
 
 // From HTML.
 declare let page: HTMLElement
-declare let moxversion: string
-declare let moxgoos: string
-declare let moxgoarch: string
 // From customization script.
 declare let moxBeforeDisplay: (webmailroot: HTMLElement) => void
 
+let moxversion: string
+let moxgoos: string
+let moxgoarch: string
+
 const login = async (reason: string) => {
 	return new Promise<string>((resolve: (v: string) => void, _) => {
 		const origFocus = document.activeElement
@@ -191,14 +192,15 @@ const crumbs = (...l: ({text: string, path: string} | string)[]) => {
 
 const errmsg = (err: unknown) => ''+((err as any).message || '(no error message)')
 
-const footer = dom.div(
-	style({marginTop: '6ex', opacity: 0.75}),
-	link('https://www.xmox.nl', 'mox'),
-	' ',
-	moxversion, ' ',
-	moxgoos, '/', moxgoarch,
-	', ', dom.a(attr.href('licenses.txt'), 'licenses')
-)
+const footer = () =>
+	dom.div(
+		style({marginTop: '6ex', opacity: 0.75}),
+		link('https://www.xmox.nl', 'mox'),
+		' ',
+		moxversion, ' ',
+		moxgoos, '/', moxgoarch,
+		', ', dom.a(attr.href('licenses.txt'), 'licenses')
+	)
 
 const age = (date: Date, future: boolean, nowSecs: number) => {
 	if (!nowSecs) {
@@ -438,7 +440,7 @@ const index = async () => {
 		dom.div(dom.a('Webserver', attr.href('#webserver'))),
 		dom.div(dom.a('Files', attr.href('#config'))),
 		dom.div(dom.a('Log levels', attr.href('#loglevels'))),
-		footer,
+		footer(),
 	)
 }
 
@@ -4249,7 +4251,7 @@ const hooksList = async () => {
 						style({textAlign: 'right'}), // Less content shifting while rendering.
 						'Sort ',
 						sortElem=dom.select(
-							attr.form('hooksfilter'), 
+							attr.form('hooksfilter'),
 							function change() {
 								filterForm.requestSubmit()
 							},
@@ -5342,6 +5344,8 @@ const webserver = async () => {
 const init = async () => {
 	let curhash: string | undefined
 
+	[moxversion, moxgoos, moxgoarch] = await client.Version()
+
 	const hashChange = async () => {
 		if (curhash === window.location.hash) {
 			return