connectors: merge the catalog page into a row-list Connectors page

The standalone Catalog page added nothing the Connectors page could not
do: drop it (component, route, sidebar entry) and move its affordances
onto the Connectors page — the Add-connector dropdown (marketplace /
manual form, now at #connectors/new) and per-row removal for the admin.

Replace the card grid with a sharper row list (4px radius) built for
scanning status and acting; the marketplace's back link now returns to
#connectors. i18n keys renamed catalog.* -> connectors.add/new/*.

web/css/connectors.css

@@ -14,6 +14,95 @@
   gap: 0.75rem;
 }
 
+/* ── Connector row list ───────────────────────────────────────────────────────
+ *
+ * The management view (the Connectors page): one row per connector, made for
+ * scanning status and acting, not browsing. It shares the cards' surface but is
+ * deliberately sharper — a 4px radius reads as a list, not a deck of cards.
+ */
+
+.connector-list {
+  display: flex;
+  flex-direction: column;
+  background:    var(--card-bg);
+  border:        1px solid var(--card-border);
+  border-radius: 4px;
+  box-shadow:    var(--card-shadow);
+}
+
+.connector-row {
+  display: flex;
+  align-items: center;
+  gap: 0.7rem;
+  padding: 0.5rem 0.75rem;
+  cursor: pointer;
+  transition: background 0.15s;
+}
+
+.connector-row + .connector-row {
+  border-top: 1px solid var(--card-border);
+}
+
+.connector-row:hover {
+  background: var(--bs-tertiary-bg);
+}
+
+.connector-row .connector-card-icon {
+  width: 28px;
+  height: 28px;
+}
+
+.connector-row-main {
+  flex: 1;
+  min-width: 0;
+}
+
+.connector-row-name {
+  display: flex;
+  align-items: baseline;
+  gap: 0.45rem;
+  min-width: 0;
+  font-weight: 600;
+  font-size: 0.88rem;
+  line-height: 1.25;
+}
+
+.connector-row-sub {
+  font-family: var(--bs-font-monospace, monospace);
+  font-size: 0.68rem;
+  font-weight: 400;
+  color: var(--placeholder-color);
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+.connector-row-desc {
+  font-size: 0.74rem;
+  color: var(--placeholder-color);
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+.connector-row-chips {
+  display: flex;
+  gap: 0.3rem;
+  flex-shrink: 0;
+}
+
+.connector-row-remove {
+  flex-shrink: 0;
+}
+
+/* On narrow widths the metadata chips crowd out the name — the status chip and
+   the detail page still carry that information. */
+@media (max-width: 720px) {
+  .connector-row-chips {
+    display: none;
+  }
+}
+
 .connector-card {
   display: flex;
   flex-direction: column;

web/css/page-shell.css

@@ -82,7 +82,6 @@ plugin-catalog-page,
 plugin-detail-page,
 plugin-page-host,
 marketplace-page,
-catalog-page,
 profile-page {
   display: none; /* toggled by JS */
   flex-direction: column;