Text field is covered by keyboard on mobile web

Previously `eframe` would shrink the canvas by an arbitrary amount to try and accomodate a mobile keyboard being shown on the bottom of the screen when the text agent was focused. This is no longer done as of:
- https://github.com/emilk/egui/pull/4561

We should come up with some alternative way to solve the issue. One potential solution is to forcefully scroll the viewport so that the input is always visible.

Start by reviewing the linked pull request #4561 and reproducing the text-input behavior on mobile web with the keyboard open. Done means the focused input remains visible without shrinking the canvas by an arbitrary amount; the issue suggests forcefully scrolling the viewport as one possible direction.

Written by the indexing model from the issue text.