Show the longest gap in the timing charts

The bar gains a faded stretch from the typical gap out to the longest one of
the window, behind the solid shortest-to-typical part. Where the solid ends is
the median, so the boundary marks "typical" without another mark on the track.

Extending the linear axis to reach it does not work. Gaps are heavily skewed —
one long overnight gap a night against daytime gaps a tenth its length — and
on a linear scale the everyday range collapsed into the first tenth of the
track, to the point that four different "since" values rendered as the same
picture. So the axis is stretched the way the sleep trend's is above 10h: the
typical gap is pinned to the middle, shortest-to-typical takes the left half
and typical-to-longest the right. Every row then reads the same way, left of
centre sooner than usual and right of centre longer, however extreme that
row's tail is. A note in the panel says as much, since a stretched axis is not
something to leave to inference.

The right edge now being the longest gap retires the old cap at twice the
typical: the marker's chevron means "past the longest gap yet" rather than
past an arbitrary cutoff.

src/changelog.json

@@ -1,4 +1,5 @@
 [
+  { "date": "2026-08-24", "text": "The timing charts now show the longest gap as well: each bar keeps its solid stretch from the shortest to the typical gap and fades on out to the longest one of the week. To stop the nightly long gap from squashing the daytime range into a sliver, the bars are stretched so the typical gap always sits dead centre — left of the middle is sooner than usual, right of it is longer, in every row" },
   { "date": "2026-08-24", "text": "Each row of the timing panel is now a small chart instead of a number: the band spans the shortest to the typical gap over the last 7 days, and the marker is how long it has been since the last one. Inside the band means there is time yet, off the right-hand end means the puppy is due — and a row with only one event so far says so instead of drawing an empty axis" },
   { "date": "2026-08-24", "text": "The timing panel now covers meals too — typical and shortest time between them, alongside the pee and poo gaps — so you can see the feeding rhythm the same way. It is titled just “Timing” now that it is no longer only about bathroom breaks" },
   { "date": "2026-08-24", "text": "The “By hour of day” chart is now tappable: tap any block to read what it counts (“3 meals between 07:00 and 08:00”) just under the chart — until now that number only showed as a hover tooltip, which phones never get. The block you tapped gets a ring" },