fix(tools): add `PfeDemoPage.js` to `package.json` exports #10543

Job	Run time
Unit Tests (Web Test Runner)	1m 14s
SSR Tests (Playwright)	1m 40s
Compile project (21)	1m 8s
Compile project (20)	1m 9s
Lint files	34s
Verify that build runs on Windows	1m 39s
Validate successful build on main	7s
Publish Playwright Report	19s
	7m 50s

Provide feedback