feat(ui): condense panels and let the window shrink to 720p

Make the job details and settings views more compact and remove the tall
minimum that prevented resizing the window shorter:

- Lay job metadata out in two columns and stack rows with a negative-gap
  compactVBoxLayout, roughly halving the block height.
- Wrap the settings form in a vertical scroll so it no longer dictates
  the window minimum (AppTabs sizes to the tallest tab), and tighten its
  rows with the same compact layout.
- Shrink the command-output scroll minimum height so the details pane can
  get shorter; long output still scrolls.
- Size the "Selected job activity" panel to exactly maxJobActivityRows
  using widget.List's own content-height formula, so all three rows show
  without a scrollbar regardless of theme or DPI.

Together these drop the minimum window height from ~891px to ~570px.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/ui/layout.go

@@ -36,6 +36,48 @@ func (l minWidthLayout) Layout(objects []fyne.CanvasObject, size fyne.Size) {
 	}
 }
 
+// compactVBoxLayout stacks children vertically with a configurable gap between
+// them, producing tighter rows than container.NewVBox (which inserts
+// theme.Padding() between every child). A negative spacing pulls neighbouring
+// rows together so they overlap the labels' built-in vertical padding, which is
+// how the details metadata is condensed to fit 720p screens.
+type compactVBoxLayout struct {
+	spacing float32
+}
+
+func (l compactVBoxLayout) MinSize(objects []fyne.CanvasObject) fyne.Size {
+	var w, h float32
+	var visible int
+	for _, o := range objects {
+		if !o.Visible() {
+			continue
+		}
+		min := o.MinSize()
+		if min.Width > w {
+			w = min.Width
+		}
+		h += min.Height
+		visible++
+	}
+	if visible > 1 {
+		h += l.spacing * float32(visible-1)
+	}
+	return fyne.NewSize(w, h)
+}
+
+func (l compactVBoxLayout) Layout(objects []fyne.CanvasObject, size fyne.Size) {
+	var y float32
+	for _, o := range objects {
+		if !o.Visible() {
+			continue
+		}
+		h := o.MinSize().Height
+		o.Move(fyne.NewPos(0, y))
+		o.Resize(fyne.NewSize(size.Width, h))
+		y += h + l.spacing
+	}
+}
+
 // fixedHeightLayout forces its contents to a fixed height while leaving the
 // width to the parent container. It is used to reserve a stable amount of space
 // for the activity panel so a neighbouring widget can absorb the rest.