fix(dashboard): heights fit content to 10px, not a whole 70px row; text columns read from the left (#5214)

View mode splits each saved row into seven, so a widget no longer carries up
to 69px of empty space below its content (Overview, SNMP). Edit mode and the
saved layout keep 70px rows. The Busiest Containers host column aligns left
like its header, its note fits one line, and the Hosts column reads Disk.

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

steward/templates/hosts/overview_widget.html

@@ -17,7 +17,7 @@
 </div>
 <table class="w-table">
   <colgroup><col><col style="width:3.6rem"><col style="width:3.6rem"><col style="width:3.6rem"><col style="width:6.5rem"></colgroup>
-  <thead><tr><th>Host</th><th>CPU</th><th>Mem</th><th>Disk /</th><th>Load</th></tr></thead>
+  <thead><tr><th>Host</th><th>CPU</th><th>Mem</th><th title="Root filesystem">Disk</th><th>Load</th></tr></thead>
   <tbody>
   {% for r in rows %}
   {% set a = r.agent %}{% set fresh = a.get('fresh') %}