- DataTable: keep `pagerNode` NULLABLE. Extracting Pager made it an always-truthy
element, so the `controls` / `bottomControls` guards always fired and a table with
nothing to page rendered empty `my-3` bands (plus an empty in-band PageToolbar).
- ChannelsProvider: `setView` bails when the tab is unchanged (re-selecting the
active tab, or goToFullHistory forcing "subscribed", stacked dead Back entries),
and pushes a FRESH state like setPage does instead of spreading `_chan`/`_yt`
markers into the tab entry.
- Lift the layout into its own narrow context (`useChannelLayout`): App read the
whole ChannelsState for the fade, so every keystroke in the manager's search box
re-rendered the app root.
- Reset the card page when the row set or sort changes (both tabs) — the clamp only
hid a stale page, which came back when the filter was cleared.
- Sort + slice the card rows only in cards mode; table mode was copy-sorting ~300
rows per render for a result nothing read.
- Validate persisted `cardSize` / `sort` (`parseCardSize`, `parseSortState`), matching
the clamp-on-read convention the module's other persisted values already follow;
a corrupt size made the page count NaN and emptied the grid.
- Pager: page-size changes scroll to the top too (they re-slice from a new first item).
- ColumnSortControl: a stored sort naming a column this table no longer offers is
treated as no sort, instead of showing a direction arrow for a sort that isn't applied.
- Drop the stale "rows" layout comments (that variant was retired this sprint).
peter
be9d17ebb1