[docs] design shuffle (#2951)

This PR incorporates design tweaks from #2922 without the home page or
content changes.

These are:
- Replacing all `hello@tldraw.com` with `sales@tldraw.com`
- Fix mailto links.
- Showing the first item in a section on direct routes to the section
- Splitting the article page for human-written content from article page
for generated content
- Splitting the layout for the landing page from the rest of the site
(temporarily identical to the regular content)
- Removing headings from left sidebar
- Restoring headings in right sidebar for human-written pages with > 1
heading link
- Styling block quote
- Adjusting section link appearance / layout in header / menu
- Changing the order of search results to preference docs over examples
- Updating copy on events
- Removing copy on user interface menus
- Adding hero as prop to all articles
- Updated icon
- Fixing a few broken links
- Replaces the sandpack code blocks with hljs code blocks, except in
examples.

### Change Type

- [x] `documentation` — Changes to the documentation only[^2]

apps/docs/scripts/functions/checkBrokenLinks.ts

@@ -1,29 +1,25 @@
 import { nicelog } from '@/utils/nicelog'
-import blc from 'broken-link-checker'
-
-const IGNORED_URLS = ['https://twitter.com/tldraw', 'https://tldraw.com']
+import { check } from 'linkinator'
 
 export async function checkBrokenLinks() {
-	nicelog('Checking broken links...')
-	const checked = new Set<string>()
-	const checker = new blc.SiteChecker(
-		{
-			filterLevel: 1,
-		},
-		{
-			link(result) {
-				if (IGNORED_URLS.includes(result.url.original)) return
-				if (checked.has(result.url.resolved)) return
-				// nicelog('Checking', result.url.resolved.replace('http://localhost:3001', ''))
-				if (result.broken) {
-					nicelog(`BROKEN: ${result.url.resolved} on page ${result.base.resolved}`)
-				}
-				checked.add(result.url.resolved)
-			},
-			end() {
-				nicelog('done')
-			},
-		}
+	const results = await check({
+		path: 'http://localhost:3001',
+		recurse: true,
+	})
+
+	// All good
+	if (results.passed) return
+
+	// There seems to be a porblem
+	nicelog(
+		`𐄂 Broken links detected!\n\n` +
+			results.links
+				.filter((result) => result.state !== 'OK')
+				.map(
+					(result, i) =>
+						`${i + 1}.\t${result.url}\n\tFrom: ${result.parent}\n\tStatus: ${result.status}`
+				)
+				.join('\n\n') +
+			'\n\n'
 	)
-	checker.enqueue('http://localhost:3001/docs/assets', null)
 }