feat(dashboard): widgets fit their content; wide screens get more grid columns (#5249)

Each widget is as tall as its content, never taller than its saved height
(where it scrolls). The dashboard is capped at 2400px instead of 1400px.
Past 12 columns' worth of width it adds columns (one per 110px, up to 24)
and places widgets again in reading order at their saved widths, so more sit
side by side instead of stretching. Edit mode shows and saves the
12-column layout, so a layout doesn't depend on the screen it was edited on.

The share view uses the same layout code (static/dash-layout.js).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/test_share_view.py

@@ -28,3 +28,13 @@ async def test_each_widget_loads_through_the_share_token(app):
     page = await _share_view(app, [item])
     assert 'hx-get="/w/hosts?id=7&s=t0ken"' in page
     assert "grid-column:1 / span 6;grid-row:3 / span 3;" in page and "every 30s" in page
+
+
+async def test_the_share_view_fits_and_widens_like_the_dashboard(app):
+    """#5249: each cell carries its saved place for static/dash-layout.js, which
+    fits it to its content and adds columns on a wide screen."""
+    gw = SimpleNamespace(id=7, grid_x=6, grid_y=2, grid_w=6, grid_h=3)
+    item = SimpleNamespace(db=gw, title="Hosts", hx_url="/w/hosts?id=7", defn=SimpleNamespace(poll=False))
+    page = await _share_view(app, [item])
+    assert 'data-id="7"' in page and 'data-x="6" data-y="2" data-w="6" data-h="3"' in page
+    assert "/static/dash-layout.js" in page and "StewardDashLayout" in page