docs(shipwrecks): describe the layer on its own, not by a layer that is not on main

Air accidents (#1584) is not merged, so comments, the changelog fragment and
CURRENT-STATE no longer explain the shipwrecks markers, card and picker by
it; the row-range test fixture is the shipwrecks row. CURRENT-STATE now says
the markers are one billboard collection and the period is stored swapped.

changelog.d/1583-shipwrecks.md

@@ -1,4 +1,4 @@
 - New Shipwrecks layer (Events): about 8,000 wrecks from EMODnet (CC BY 4.0)
   and Wikidata (CC0). Each has a card with deaths, date, vessel, cause, depth,
   position quality and a source link. Markers grow with the death toll, and
-  the same period picker as air accidents filters by year (IMBrandao, #1583).
+  a start and end year picker filters by period (IMBrandao, #1583).

docs/CURRENT-STATE.md

@@ -170,14 +170,15 @@ read: EMODnet's long histories (`ship_char`, `obj_desc`) are not, and any
 sinking or cargo text that names a person (owner, master, a diver who reported
 it) is dropped whole; deaths appear only as a Wikidata count.
 
-The globe draws a round marker with a hull and mast per wreck, ground-clamped
+The globe draws a round marker with a hull and mast per wreck, all in one
-with the depth test off and the horizon cull GhostMaps uses, sized by deaths as
+billboard collection, ground-clamped with the depth test off and the horizon
-on Air accidents and coloured by era (a legend under the row): before 1900
+cull GhostMaps uses, sized by deaths (a bigger toll draws on top) and coloured
+by era (a legend under the row): before 1900
 (ancient wrecks dated only by period count here), 1900–1945, after 1945, and
 date unknown. A period filter under the row picks a start year and an end year
-side by side, the same control as Air accidents (two pickers over the years in
+side by side (two pickers over the years in the data; a reversed pair is
-the data; a reversed pair is swapped); undated wrecks show only when every year
+stored swapped); undated wrecks show only when every year
-is selected. The filter is session-only (not in the share link). Clicking a marker opens a `stateless` card laid out like the air-accident card: deaths and
+is selected. The filter is session-only (not in the share link). Clicking a marker opens a `stateless` card: deaths and
 survivors first, then the sinking date or year (or the archaeological dating) and
 waters, vessel type, what happened,
 least depth and its quality, how well the position is known, period notes or

src/layers/shipwrecks/cards.js

@@ -54,8 +54,7 @@ export function cardLink(record) {
 }
 
 /**
- * Title and detail lines for one wreck card, laid out like the air-accident
+ * Title and detail lines for one wreck card: deaths first, then when and where, then the ship facts. Only facts
- * card: deaths first, then when and where, then the ship facts. Only facts
  * about the ship: the records carry no names of people, and victims appear as
  * a count only.
  * @param {object} record A normalized shipwreck record.

src/layers/shipwrecks/index.js

@@ -30,8 +30,7 @@ const CARD_HOST_OPTIONS = Object.freeze({
 });
 const MAX_CARD_LINES = 14;
 /**
- * Marker size in pixels: grows with the death toll, as on the air-accidents
+ * Marker size in pixels: grows with the death toll, from 16 px (no deaths known) to 36 px (about a thousand or more).
- * layer, from 16 px (no deaths known) to 36 px (about a thousand or more).
  */
 export function markerPixelSize(casualties) {
   const n = Number.isFinite(casualties) && casualties > 0 ? casualties : 0;
@@ -285,7 +284,7 @@ export function createShipwrecksLayer({
     return count;
   }
 
-  /** The start and end year pickers, side by side, as on Air accidents. */
+  /** The start and end year pickers, side by side. */
   function periodControls() {
     if (!_extent || _extent.min === _extent.max) return {};
     const range = periodRange(_period, _extent);

src/ui/layerPanel/RowRange.vue

@@ -1,5 +1,5 @@
 <script setup>
-// A row's start and end pickers on one line (e.g. the Air Accidents period).
+// A row's start and end pickers on one line (e.g. the Shipwrecks period).
 // Both ends share one option list; `onSelect` reports which end moved
 // ('from' or 'to') and the chosen option value.
 defineProps({

src/ui/layerPanel/layerRows.test.mjs

@@ -166,8 +166,8 @@ test('a row range renders start and end pickers and reports which end moved', ()
   const picks = [];
   const item = {
     ...row(false),
-    key: 'air-accidents',
+    key: 'shipwrecks',
-    id: 'air-accidents',
+    id: 'shipwrecks',
     controls: {
       hidden: false,
       chips: [],
@@ -215,6 +215,6 @@ test('a row range renders start and end pickers and reports which end moved', ()
   );
   to.value = '2007';
   to.dispatchEvent(new Event('change', { bubbles: true }));
-  assert.deepEqual(picks, [['air-accidents', 'period', 'to', '2007']]);
+  assert.deepEqual(picks, [['shipwrecks', 'period', 'to', '2007']]);
   render(null, container);
 });

src/ui/styles/radio.css

@@ -1067,7 +1067,7 @@ html:not([lang='en']) .data-row-list-text {
   letter-spacing: 0.8px;
 }
 
-/* Optional start and end pickers on one line (Air Accidents period). The
+/* Optional start and end pickers on one line (e.g. a layer's period). The
    shared field style paints each select. */
 .data-toggle-range {
   flex-basis: 100%;