feat(dashboard): widget readability — name-per-line, fill graphs, container breakpoints

Address graphical issues raised from the dashboard screenshot:
- No more truncated host names. Hosts-Overview and Host-Agent-Resources put the
  host name on its own line (full, wraps if needed) with its data grouped beneath
  it; ping/dns (.ping-name) and uptime widget names wrap instead of ellipsis.
  Prefer vertical overflow over cramming/truncating a row.
- History graph fills the panel: drop the fixed 0–100 y-axis ceiling (beginAtZero
  + 8% grace) so the lines use the vertical space instead of hugging the bottom;
  axis labels still show real %.
- Container-query breakpoints: the widget body is now a query container, so
  fragments restyle to their OWN panel width. Host-list widgets flow into 2 cols
  ≥520px and 3 cols ≥900px (.host-blocks) — use the width, remove vertical
  deadspace — and collapse to one column when narrow. Mirrored into the share view.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

steward/templates/base.html

@@ -163,7 +163,7 @@ textarea { resize: vertical; }
 .ping-row { display:flex; align-items:center; gap:1rem; padding:0.45rem 0; border-bottom:1px solid var(--border); }
 .ping-row:last-child { border-bottom:none; }
 .ping-meta { min-width:120px; max-width:180px; flex-shrink:1; overflow:hidden; }
-.ping-name { font-size:0.875rem; font-weight:500; white-space:nowrap; overflow:hidden; text-overflow:ellipsis; display:block; }
+.ping-name { font-size:0.875rem; font-weight:500; display:block; overflow-wrap:anywhere; }
 a.ping-name:hover { text-decoration:underline; }
 /* Dashboard widget grid — Gridstack-rendered. Static (positioned but inert) in
    view mode; the dashboard itself becomes the edit surface when Edit is toggled,
@@ -174,6 +174,14 @@ a.ping-name:hover { text-decoration:underline; }
   padding:0.8rem 1rem; display:flex; flex-direction:column; overflow:hidden;
 }
 .grid-stack-item-content .dash-cell-body { flex:1; min-height:0; overflow:auto; }
+/* The widget body is a query container, so fragments can restyle to their OWN
+   panel width (not the viewport) — widgets adapt as you resize them. */
+.dash-cell-body { container-type:inline-size; }
+/* Host-list widgets flow into columns as the panel widens: use the width, drop
+   the vertical deadspace; stay single-column (and untruncated) when narrow. */
+.host-blocks { display:grid; grid-template-columns:1fr; gap:0 1.5rem; }
+@container (min-width:520px) { .host-blocks { grid-template-columns:1fr 1fr; } }
+@container (min-width:900px) { .host-blocks { grid-template-columns:1fr 1fr 1fr; } }
 .panel-chrome { display:none; }
 .panel-drag { cursor:grab; color:var(--text-dim); user-select:none; }
 .panel-drag:active { cursor:grabbing; }