Add XML documentation for Android.Widget.Inline

The `Android.Widget.Inline` namespace contains **37** `To be added` placeholders in source XML documentation (excluding `docs\xml\index.xml`).

```powershell
rg -n -i --glob 'Android.Widget.Inline/**' --glob 'ns-Android.Widget.Inline.xml' 'to be added' docs\xml
```

## Update log

- 2026-09-10: Refreshed the placeholder scan from **62** to **37** (reduced by **25**). Related documentation PRs: [#436](https://github.com/dotnet/android-api-docs/pull/436), [#644](https://github.com/dotnet/android-api-docs/pull/644).

Start in docs\xml and run the issue's ripgrep command to locate the 37 remaining `To be added` placeholders under Android.Widget.Inline, excluding docs\xml\index.xml. Review the surrounding source XML documentation and replace each placeholder with appropriate reference text. Done means the scan no longer finds placeholders in the specified namespace.

Written by the indexing model from the issue text.