PC Detail: flow Details cards, drop the IP Configuration card

Details tab card layout
-----------------------
The Details tab sat on .content-grid, a two-column CSS grid. Grid packs
items into implicit rows, so every row is as tall as its tallest card and
align-items:start leaves the shorter one with dead space beneath it:
Warranty is short, Endpoint Status is tall, and Policy had to wait for the
taller of the two rather than sliding up. That read as a staggered layout.

Switched that one tab to multicol via a .details-flow modifier, which has no
rows at all - each card starts where the previous one ended, so the holes
close while cards still size to their content.

Multicol is deliberately NOT applied to .content-grid globally. The note by
that rule in style.css records why it was abandoned there: a column-span:all
child (.pap-span, used by table panels) overlaps the shorter column when the
two are unequal. That cannot happen on this tab - every panel in the details
group is a keyvalue or list render, and spansFullWidth() only returns true
for table (or a tabs panel holding one), so nothing in the subtree spans.
Monitors and Service/Process DO carry table panels and stay on grid.

The modifier is scoped to PCDetail, so the nine other detail views on
.content-grid are untouched.

Chosen over JS masonry on purpose. Masonry packs perfectly but has to
measure every card and re-measure on resize, on panel collapse and on every
async panel load - and these panels fetch after paint, so it would mean
continuous forced reflow on a page that already polls. This is pure CSS:
no measurement, no observer, no runtime cost. The tradeoff accepted is that
column bottoms can end at slightly different heights.

Cards carry break-inside: avoid so none fragments across the column break,
and the 25px spacing returns as a margin because multicol has no gap between
stacked items the way grid does.

IP Configuration card
---------------------
Removed: the data has no purpose on the page anymore. Taken out at the root
rather than hidden - the panel declaration, the /asset/<id>/ipconfig route
and the _IPCONFIG_COLUMNS constant all go, since a route with no consumer is
dead surface that still answers requests.

test_the_two_cards_do_not_duplicate_columns_beyond_the_address existed only
to police the history/config column split; with one card gone it guards
nothing, so it and its import go with it. The panel-count assertion in
test_endpoints_asset_panels_are_computer_scoped moves 15 -> 14, which is the
test doing its job and catching the removal.

IP History is unchanged and still carries the address list.

Not addressed here: three tzset() tests in test_endpoints_plugin.py fail on
Windows because time.tzset() is Unix-only. Verified pre-existing against
unmodified code; they pass in the Linux container.

tests/test_plugins/test_endpoints_ip_history.py

@@ -15,7 +15,6 @@ from datetime import datetime
 from pathlib import Path
 
 from plugins.endpoints.api.routes import (
-    _IPCONFIG_COLUMNS,
     _IPHISTORY_COLUMNS,
     _iphistory_status,
     _isostamp,
@@ -95,15 +94,6 @@ def test_the_second_date_is_not_labelled_last_seen():
     assert labels['firstseen'] == 'First seen'
 
 
-def test_the_two_cards_do_not_duplicate_columns_beyond_the_address():
-    # They are split so neither is eleven columns wide. The address is the
-    # deliberate join between them; anything else repeated means the split
-    # drifted back together.
-    history = {col['key'] for col in _IPHISTORY_COLUMNS}
-    config = {col['key'] for col in _IPCONFIG_COLUMNS}
-    assert history & config == {'ipaddress'}
-
-
 def test_the_history_ordering_compiles_on_mysql():
     # Regression: the first cut ordered with .nullslast(), which is valid
     # ANSI/Postgres but blows up on MySQL with a 1064 syntax error. The test

tests/test_plugins/test_endpoints_plugin.py

@@ -69,7 +69,7 @@ def test_endpoints_asset_panels_are_computer_scoped():
     """Every asset panel targets computer assets only, with an endpoint."""
     plugin = EndpointsPlugin()
     panels = plugin.get_asset_panels()
-    assert len(panels) == 15
+    assert len(panels) == 14
     for panel in panels:
         assert panel['assettypes'] == ['computer']
         assert panel['endpoint'].startswith('/api/endpoints/')