fix(components): take the section header's metrics from Calendula's

The header was invented here rather than converged from the app that
already had one. Calendula's SectionHeader is labelLarge at top 16 /
bottom 4, and separates one group from the next with the caller's own 8dp
spacer — a hub's first header follows the About card, not another group,
so the gap cannot live on the header. Matched exactly, so the two apps'
settings hubs are the same page.

CHANGELOG.md

@@ -13,11 +13,11 @@ are no binary releases; "version" tracks the shared `version` in the root build
 ### Added
 
 - **`components`** — `GroupedSectionHeader`, the label above a run of
-  `GroupedRow`s. Starts on `GroupedListInset` and owns the gap to the group
-  above, so a page writes header-then-rows and nothing else; `primary`, after
-  the Android-15 settings pattern the row system already follows. Wanted by
-  Agendula's settings hub, which had grown a flat run of a dozen rows with
-  nothing separating how the app behaves from what it is.
+  `GroupedRow`s: small, `primary`, inset to `GroupedListInset` so it shares the
+  cards' left margin. Converged from Calendula's settings hub, where the recipe
+  was written as a private `SectionHeader`, and now Agendula's, which had grown
+  a flat run of a dozen rows with nothing separating how the app behaves from
+  what it is.
 
 - **`components`** — `GroupedRow` takes a `contentColor`, the pair to the
   existing `container`: a row given a tint now names the `on*` role that goes

components/src/main/kotlin/de/jeanlucmakiola/floret/components/GroupedList.kt

@@ -58,24 +58,23 @@ val GroupedListInset = 16.dp
  * rather than merely spaced apart — a settings hub that separates how the app
  * behaves from what it is.
  *
- * Starts on [GroupedListInset], the same edge as the cards it names, and owns
- * the space that separates its group from the one above, so a caller writes
- * header-then-rows and nothing else. Coloured `primary` after the Android-15
- * settings pattern this row system already follows: the headers are what makes
- * the grouping readable at a glance, and `onSurfaceVariant` sinks them into the
- * summaries.
+ * Small, `primary`, and inset to [GroupedListInset] so it shares the left
+ * margin of the cards it names. Converged from Calendula's settings hub, where
+ * the recipe was written; a caller separates one group from the next with its
+ * own 8dp spacer, since a hub's first header follows the About card rather than
+ * another group.
  */
 @Composable
 fun GroupedSectionHeader(text: String, modifier: Modifier = Modifier) {
     Text(
         text = text,
-        style = MaterialTheme.typography.titleSmall,
+        style = MaterialTheme.typography.labelLarge,
         color = MaterialTheme.colorScheme.primary,
         modifier = modifier.padding(
             start = GroupedListInset,
             end = GroupedListInset,
-            top = 24.dp,
-            bottom = 8.dp,
+            top = 16.dp,
+            bottom = 4.dp,
         ),
     )
 }