fix(app): align schedules screen shell with app conventions

Move the New schedule button out of the screen header (the only screen
using MenuHeader rightContent) into the content filter row, and match the
History screen's full-width layout instead of the 720px centered column.

Tighten the shared sm SegmentedControl and Button vertical padding so the
status switcher and button sit flush with the host-filter pill; this is a
global sm change and also affects settings and the schedule form sheet.

packages/app/src/components/ui/button.tsx

@@ -50,7 +50,7 @@ const styles = StyleSheet.create((theme) => ({
     borderRadius: theme.borderRadius.md,
   },
   sm: {
-    paddingVertical: theme.spacing[2],
+    paddingVertical: theme.spacing[1.5],
     paddingHorizontal: theme.spacing[3],
     borderRadius: theme.borderRadius.md,
   },

packages/app/src/components/ui/segmented-control.tsx

@@ -161,7 +161,7 @@ const styles = StyleSheet.create((theme) => ({
     gap: theme.spacing[1],
   },
   segmentSm: {
-    paddingVertical: theme.spacing[2],
+    paddingVertical: theme.spacing[1.5],
     paddingHorizontal: theme.spacing[4],
   },
   segmentMd: {