cab003c85820ef181c537ad402aad0044e4e3878
braney
  Tue Sep 1 09:06:56 2026 -0700
registryPages: draw two pages from all four configuration catalogs, refs #37838 #37923 #37925 #37623

Each of the four catalogs answers for its own surface and none of them knows
the others exist.  This reads all four and draws the two pages that need them
at once: a Venn of the registries, and an index of every name they describe
with its description on hover.

The reason it is a program and not two files: every count on both pages is
computed from the catalogs, so a page cannot drift from the tree.  A hand-built
version of the Venn had the track registry 12 names short and one region count
wrong, and neither error was visible on the page.

The one judgement is which names two registries describe as the same variable.
That is matched on the cart variable a row names, not on the suffix the track
catalog stores, because comparing bare names both misses the four track-scoped
names and invents six overlaps that are not there.  KNOWN_SHARED records the
eleven confirmed by reading the call sites, and --check fails when the computed
set no longer matches it, the same contract the sibling catalogs' --reconcile
has.

--check writes nothing and is the mode for a cron.  --audit adds the saved
session counts from sessionCartAudit and needs the database.

diff --git src/hg/utils/registryPages/venn.css src/hg/utils/registryPages/venn.css
new file mode 100644
index 00000000000..589d2c88d8e
--- /dev/null
+++ src/hg/utils/registryPages/venn.css
@@ -0,0 +1,125 @@
+:root{
+  color-scheme: light;
+  --bg:#f4f6f8; --panel:#ffffff; --ink:#131a20; --ink2:#4a5a66; --ink3:#7c8b95;
+  --rule:#dbe2e8; --rule2:#eaeff3;
+  --s-track:#e87ba4; --s-url:#2a78d6; --s-file:#008300; --s-conf:#eda100;
+  --fill:0.11;
+  --display:"Archivo","Helvetica Neue",Arial,sans-serif;
+  --body:"IBM Plex Serif",Georgia,"Times New Roman",serif;
+  --mono:"IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
+}
+@media (prefers-color-scheme: dark){
+  :root:not([data-theme="light"]){
+    color-scheme: dark;
+    --bg:#171a1d; --panel:#1e2226; --ink:#e9edf1; --ink2:#a8b4bd; --ink3:#7b8891;
+    --rule:#2d353b; --rule2:#262d33;
+    --s-track:#d55181; --s-url:#3987e5; --s-file:#008300; --s-conf:#c98500;
+    --fill:0.17;
+  }
+}
+:root[data-theme="dark"]{
+  color-scheme: dark;
+  --bg:#171a1d; --panel:#1e2226; --ink:#e9edf1; --ink2:#a8b4bd; --ink3:#7b8891;
+  --rule:#2d353b; --rule2:#262d33;
+  --s-track:#d55181; --s-url:#3987e5; --s-file:#008300; --s-conf:#c98500;
+  --fill:0.17;
+}
+
+*{box-sizing:border-box}
+a{color:inherit; text-underline-offset:3px; text-decoration-thickness:1px; text-decoration-color:var(--s-url)}
+a:hover{text-decoration-color:currentColor}
+a:focus-visible{outline:2px solid var(--s-url); outline-offset:2px; border-radius:2px}
+body{
+  background:var(--bg); color:var(--ink);
+  font-family:var(--body); font-size:16.5px; line-height:1.62;
+  -webkit-font-smoothing:antialiased;
+}
+.wrap{max-width:1060px; margin:0 auto; padding:44px 24px 96px; display:flex; flex-direction:column; gap:44px}
+
+/* ---------- header ---------- */
+.eyebrow{
+  font-family:var(--mono); font-size:11.5px; font-weight:500; letter-spacing:.14em;
+  text-transform:uppercase; color:var(--ink3); margin:0 0 14px;
+}
+h1{
+  font-family:var(--display); font-weight:700; font-size:clamp(34px,5.4vw,54px);
+  line-height:1.04; letter-spacing:-0.02em; margin:0 0 18px; text-wrap:balance;
+}
+.lede{max-width:63ch; margin:0; color:var(--ink2); font-size:18px}
+.lede strong{color:var(--ink); font-weight:600}
+.meta{
+  margin-top:22px; padding-top:16px; border-top:1px solid var(--rule);
+  font-family:var(--mono); font-size:12px; color:var(--ink3);
+  display:flex; flex-wrap:wrap; gap:8px 26px;
+}
+
+/* ---------- figure ---------- */
+figure{margin:0; background:var(--panel); border:1px solid var(--rule); border-radius:3px; padding:26px 22px 20px}
+.svg-scroll{overflow-x:auto}
+svg.venn{display:block; width:100%; min-width:640px; height:auto}
+figcaption{
+  margin-top:18px; padding-top:14px; border-top:1px solid var(--rule2);
+  color:var(--ink2); font-size:14.5px; max-width:70ch;
+}
+
+.r-count{font-family:var(--display); font-weight:700; fill:var(--ink)}
+.r-name{font-family:var(--mono); font-weight:500; font-size:11px; letter-spacing:.1em; fill:var(--ink2)}
+.r-zero{font-family:var(--display); font-weight:500; font-size:13px; fill:var(--ink3)}
+.r-small{font-family:var(--display); font-weight:700; font-size:19px; fill:var(--ink)}
+.tick{font-family:var(--mono); font-size:10.5px; fill:var(--ink3); letter-spacing:.06em}
+
+/* ---------- sections ---------- */
+h2{
+  font-family:var(--display); font-weight:600; font-size:22px; letter-spacing:-0.01em;
+  margin:0 0 6px;
+}
+.sub{margin:0 0 22px; color:var(--ink2); font-size:15.5px; max-width:68ch}
+section{display:flex; flex-direction:column}
+
+/* shared-name list */
+.slivers{display:flex; flex-direction:column; gap:0; border-top:1px solid var(--rule)}
+.sliver{
+  display:grid; grid-template-columns:200px 1fr; gap:6px 28px;
+  padding:20px 0; border-bottom:1px solid var(--rule);
+}
+.sliver-head{display:flex; flex-direction:column; gap:8px}
+.pairchips{display:flex; align-items:center; gap:7px}
+.chip{width:11px; height:11px; border-radius:2px; flex:none}
+.chip.track{background:var(--s-track)} .chip.url{background:var(--s-url)}
+.chip.file{background:var(--s-file)} .chip.conf{background:var(--s-conf)}
+.pairname{font-family:var(--mono); font-size:11.5px; letter-spacing:.07em; text-transform:uppercase; color:var(--ink2)}
+.pairnum{font-family:var(--display); font-weight:700; font-size:30px; line-height:1}
+.pairnum span{font-family:var(--mono); font-weight:400; font-size:12px; color:var(--ink3); letter-spacing:.06em; margin-left:7px}
+ul.names{list-style:none; margin:0; padding:0; display:flex; flex-direction:column; gap:11px}
+ul.names li{display:flex; flex-wrap:wrap; gap:4px 12px; align-items:baseline}
+code{font-family:var(--mono); font-size:13.5px; background:var(--rule2); padding:1.5px 6px; border-radius:2px; white-space:nowrap}
+.note{color:var(--ink2); font-size:14.5px; flex:1 1 260px; min-width:0}
+
+/* table */
+.tablewrap{overflow-x:auto; border:1px solid var(--rule); border-radius:3px; background:var(--panel)}
+table{border-collapse:collapse; width:100%; font-size:14px}
+caption{text-align:left; padding:14px 16px; color:var(--ink3); font-family:var(--mono); font-size:11.5px; letter-spacing:.1em; text-transform:uppercase; border-bottom:1px solid var(--rule)}
+th,td{padding:9px 16px; text-align:left; border-bottom:1px solid var(--rule2)}
+th{font-family:var(--mono); font-weight:500; font-size:11px; letter-spacing:.09em; text-transform:uppercase; color:var(--ink3)}
+td.num{text-align:right; font-family:var(--mono); font-variant-numeric:tabular-nums}
+tbody tr:last-child td{border-bottom:none}
+tr.z td{color:var(--ink3)}
+.dots{display:inline-flex; gap:4px; vertical-align:middle}
+.dot{width:9px; height:9px; border-radius:50%}
+.dot.off{background:transparent; box-shadow:inset 0 0 0 1px var(--rule)}
+.dot.track{background:var(--s-track)} .dot.url{background:var(--s-url)}
+.dot.file{background:var(--s-file)} .dot.conf{background:var(--s-conf)}
+
+/* notes */
+.notes{display:grid; grid-template-columns:repeat(auto-fit,minmax(280px,1fr)); gap:26px}
+.notecard{border-top:2px solid var(--rule); padding-top:14px}
+.notecard h3{font-family:var(--display); font-weight:600; font-size:15px; margin:0 0 8px; letter-spacing:-0.005em}
+.notecard p{margin:0 0 10px; font-size:14.5px; color:var(--ink2)}
+.notecard p:last-child{margin-bottom:0}
+
+footer{border-top:1px solid var(--rule); padding-top:18px; font-family:var(--mono); font-size:11.5px; color:var(--ink3); line-height:1.8}
+
+@media (max-width:640px){
+  .sliver{grid-template-columns:1fr}
+  .wrap{gap:38px; padding:32px 18px 72px}
+}