unbrivate, dot com in (#2475)

This PR moves the tldraw.com app into the public repo.

### Change Type

- [x] `internal` — Any other changes that don't affect the published
package[^2]

---------

Co-authored-by: Dan Groshev <git@dgroshev.com>
Co-authored-by: alex <alex@dytry.ch>

scripts/lib/makeEnv.ts

@@ -0,0 +1,18 @@
+export function makeEnv<const Keys extends readonly string[]>(
+	keys: Keys
+): Record<Keys[number], string> {
+	const env = {} as Record<string, string>
+	const missingVars = []
+	for (const key of keys) {
+		const value = process.env[key]
+		if (value === undefined) {
+			missingVars.push(key)
+			continue
+		}
+		env[key] = value
+	}
+	if (missingVars.length > 0) {
+		throw new Error(`Missing environment variables: ${missingVars.join(', ')}`)
+	}
+	return env as Record<Keys[number], string>
+}