WASM Sample App should update URL and provide links to specific samples

### Describe the bug

If you click on a specific sample at https://toolkitlabs.dev/ the url doesn't update, so you can't share a link to that specific sample page.

We need to:
- Have the URL update with information about the documentation page loaded
- Be able to process a non-root url and navigate to that page on launch
- Handle cases where that path is invalid and display a nice 404 page and have buttons to go to the home page, the Labs repo, the Toolkit documentation and Toolkit repo (as likely the experiment has moved to the main toolkit?)
- Later maybe we want a mechanism for redirection if we know that is the case and can leave a stub metadata file or something somewhere that's non-invasive to the Labs repo?
- P2: If I select a specific sample from the drop-down (or have it in view) update url with an anchor `#` so that I can link to that sample, e.g. `https://toolkitlabs.dev/contentsizer#leftsideshelf` (don't think we want to have category/sub in url so we can re-organize later without breaking links)

### Steps to reproduce

```text
1. Go to toolkitlabs.dev
2. Click on a page
3. Look at URL
```

### Expected behavior

See unique URL, able to copy it and share, open to that specific page when used.

### Screenshots

_No response_

### Code Platform

- [ ] UWP
- [ ] WinAppSDK / WinUI 3
- [X] Web Assembly (WASM)
- [ ] Android
- [ ] iOS
- [ ] MacOS
- [ ] Linux / GTK

### Windows Build Number

- [ ] Windows 10 1809 (Build 17763)
- [ ] Windows 10 1903 (Build 18362)
- [ ] Windows 10 1909 (Build 18363)
- [ ] Windows 10 2004 (Build 19041)
- [ ] Windows 10 20H2 (Build 19042)
- [ ] Windows 10 21H1 (Build 19043)
- [ ] Windows 11 21H2 (Build 22000)
- [ ] Other (specify)

### Other Windows Build number

_No response_

### App minimum and target SDK version

- [ ] Windows 10, version 1809 (Build 17763)
- [ ] Windows 10, version 1903 (Build 18362)
- [ ] Windows 10, version 1909 (Build 18363)
- [ ] Windows 10, version 2004 (Build 19041)
- [ ] Other (specify)

### Other SDK version

_No response_

### Visual Studio Version

_No response_

### Visual Studio Build Number

_No response_

### Device form factor

_No response_

### Additional context

_No response_

### Help us help you

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