Improve component data table UI in the selection panel (#4370)

### What

Improve the UI of component data tables in the selection panel. The
behaviour now depends on how many items are selected. If only one is
selected, the table expends to the max and relies on the selection
panel's `ScrollArea`.

* Fixes #3228

### Screenshots

Single selection:

<img width="376" alt="image"
src="https://github.com/rerun-io/rerun/assets/49431240/54eb33b7-21f0-4858-9030-f91ea3df1b53">

Multiple selections:

<img width="384" alt="image"
src="https://github.com/rerun-io/rerun/assets/49431240/d872c788-4bba-4ed2-b1cf-1566198fe05c">

Hover tooltip are still compact:

<img width="197" alt="image"
src="https://github.com/rerun-io/rerun/assets/49431240/55e9217a-c9e4-41b0-8d26-96f35c6a24f3">

### Checklist
* [x] I have read and agree to [Contributor
Guide](https://github.com/rerun-io/rerun/blob/main/CONTRIBUTING.md) and
the [Code of
Conduct](https://github.com/rerun-io/rerun/blob/main/CODE_OF_CONDUCT.md)
* [x] I've included a screenshot or gif (if applicable)
* [x] I have tested [app.rerun.io](https://app.rerun.io/pr/4370) (if
applicable)
* [x] The PR title and labels are set such as to maximize their
usefulness for the next release's CHANGELOG

- [PR Build Summary](https://build.rerun.io/pr/4370)
- [Docs
preview](https://rerun.io/preview/e51649c650146ac58f3d8df776e242b86ceb5849/docs)
<!--DOCS-PREVIEW-->
- [Examples
preview](https://rerun.io/preview/e51649c650146ac58f3d8df776e242b86ceb5849/examples)
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- [Recent benchmark results](https://build.rerun.io/graphs/crates.html)
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crates/re_data_ui/src/component.rs

@@ -97,13 +97,28 @@ impl DataUi for EntityComponentWithInstances {
                 re_format::format_number(num_instances)
             ));
         } else {
-            egui_extras::TableBuilder::new(ui)
+            let mut table = egui_extras::TableBuilder::new(ui)
                 .resizable(false)
-                .vscroll(true)
-                .auto_shrink([true, true])
-                .max_scroll_height(100.0)
                 .cell_layout(egui::Layout::left_to_right(egui::Align::Center))
-                .columns(egui_extras::Column::auto(), 2)
+                .columns(egui_extras::Column::auto(), 2);
+
+            if verbosity == UiVerbosity::All {
+                // Use full width in the selection panel.
+                table = table.auto_shrink([false, true]);
+            } else {
+                // Be as small as possible in the hover tooltips.
+                table = table.auto_shrink([true, true]);
+            }
+
+            if verbosity == UiVerbosity::All && ctx.selection().len() <= 1 {
+                // We're alone in the selection panel. Let the outer ScrollArea do the work.
+                table = table.vscroll(false);
+            } else {
+                // Don't take too much vertical space to leave room for other selected items.
+                table = table.vscroll(true).max_scroll_height(100.0);
+            }
+
+            table
                 .header(re_ui::ReUi::table_header_height(), |mut header| {
                     re_ui::ReUi::setup_table_header(&mut header);
                     header.col(|ui| {