fix(onboarding): 44px touch targets across wizard CTAs + carousel pager

Bring every back / skip / next / chevron / pager button on the
v1.4.25 onboarding wizard up to the 44x44 px WCAG 2.5.8 floor. The
previous `size="sm"` buttons measured 32 px tall, the chevron icons
were 32 px square, and each dot pager target was 10 px square — all
well under the target-size minimum for thumb-driven flows.

Carousel slides now derive their accessible name from the slide
title via `aria-labelledby`, so the polite live region (which
mirrors "Slide N of M") is the single source for position
announcements. The previous markup announced position twice on every
swipe: once from the slide's own `aria-label`, again from the
live region.

src/components/onboarding/BaselineForm.tsx

@@ -197,16 +197,16 @@ export function BaselineForm() {
       </fieldset>
 
       <div className="flex items-center justify-between gap-2 pt-2">
-        <Button asChild variant="ghost" size="sm">
+        <Button asChild variant="ghost" className="min-h-11 min-w-11">
           <Link href="/onboarding/2">{t("onboarding.shell.back")}</Link>
         </Button>
         <div className="flex items-center gap-2">
           <Button
             type="button"
             variant="ghost"
-            size="sm"
             onClick={() => advance({ saveProfile: false })}
             disabled={saving}
+            className="min-h-11 min-w-11"
           >
             {t("onboarding.shell.skip")}
           </Button>
@@ -214,6 +214,7 @@ export function BaselineForm() {
             type="button"
             onClick={() => advance({ saveProfile: true })}
             disabled={saving}
+            className="min-h-11 min-w-11"
           >
             {saving ? <Loader2 className="size-4 animate-spin" /> : null}
             {t("onboarding.baseline.saveCta")}

src/components/onboarding/GoalsChipPicker.tsx

@@ -249,20 +249,25 @@ export function GoalsChipPicker({ userId }: GoalsChipPickerProps) {
       </fieldset>
 
       <div className="flex items-center justify-between gap-2 pt-2">
-        <Button asChild variant="ghost" size="sm">
+        <Button asChild variant="ghost" className="min-h-11 min-w-11">
           <Link href="/onboarding/0">{t("onboarding.shell.back")}</Link>
         </Button>
         <div className="flex items-center gap-2">
           <Button
             type="button"
             variant="ghost"
-            size="sm"
             onClick={advance}
             disabled={advancing}
+            className="min-h-11 min-w-11"
           >
             {t("onboarding.shell.skip")}
           </Button>
-          <Button type="button" onClick={advance} disabled={advancing}>
+          <Button
+            type="button"
+            onClick={advance}
+            disabled={advancing}
+            className="min-h-11 min-w-11"
+          >
             {t("onboarding.shell.next")}
           </Button>
         </div>

src/components/onboarding/OnboardingShell.tsx

@@ -135,7 +135,7 @@ export async function OnboardingShell({
 
       <footer className="mt-8 flex items-center justify-between gap-2">
         {backHref ? (
-          <Button asChild variant="ghost" size="sm">
+          <Button asChild variant="ghost" className="min-h-11 min-w-11">
             <Link href={backHref}>{t("onboarding.shell.back")}</Link>
           </Button>
         ) : (
@@ -144,12 +144,12 @@ export async function OnboardingShell({
 
         <div className="flex items-center gap-2">
           {skipHref ? (
-            <Button asChild variant="ghost" size="sm">
+            <Button asChild variant="ghost" className="min-h-11 min-w-11">
               <Link href={skipHref}>{t("onboarding.shell.skip")}</Link>
             </Button>
           ) : null}
           {nextHref ? (
-            <Button asChild size="sm">
+            <Button asChild className="min-h-11 min-w-11">
               <Link href={nextHref}>{primaryLabel}</Link>
             </Button>
           ) : null}

src/components/onboarding/SourceCardGrid.tsx

@@ -152,20 +152,25 @@ export function SourceCardGrid() {
       </div>
 
       <div className="flex items-center justify-between gap-2 pt-2">
-        <Button asChild variant="ghost" size="sm">
+        <Button asChild variant="ghost" className="min-h-11 min-w-11">
           <Link href="/onboarding/1">{t("onboarding.shell.back")}</Link>
         </Button>
         <div className="flex items-center gap-2">
           <Button
             type="button"
             variant="ghost"
-            size="sm"
             onClick={advance}
             disabled={advancing}
+            className="min-h-11 min-w-11"
           >
             {t("onboarding.shell.skip")}
           </Button>
-          <Button type="button" onClick={advance} disabled={advancing}>
+          <Button
+            type="button"
+            onClick={advance}
+            disabled={advancing}
+            className="min-h-11 min-w-11"
+          >
             {t("onboarding.shell.next")}
           </Button>
         </div>

src/components/onboarding/WelcomeCarousel.tsx

@@ -181,10 +181,7 @@ export function WelcomeCarousel() {
               data-slide-index={idx}
               role="group"
               aria-roledescription="slide"
-              aria-label={t("onboarding.welcome.slideOf", {
-                current: idx + 1,
-                total: SLIDES.length,
-              })}
+              aria-labelledby={`onboarding-welcome-slide-${slide.id}-title`}
               className={cn(
                 "bg-card border-border flex w-full shrink-0 snap-start flex-col items-center gap-4",
                 "rounded-xl border p-6 text-center sm:p-8",
@@ -196,7 +193,10 @@ export function WelcomeCarousel() {
               >
                 <slide.Icon className="size-8" />
               </span>
-              <h2 className="text-lg font-semibold tracking-tight">
+              <h2
+                id={`onboarding-welcome-slide-${slide.id}-title`}
+                className="text-lg font-semibold tracking-tight"
+              >
                 {t(slide.titleKey)}
               </h2>
               <p className="text-muted-foreground text-sm leading-relaxed">
@@ -206,9 +206,11 @@ export function WelcomeCarousel() {
           ))}
         </div>
 
-        {/* Live region announces slide changes to AT users — matches the
-            tour's pattern (tour.tsx:374) so the focus contract is
-            consistent across the onboarding surface. */}
+        {/* Single live region announces slide changes to AT users —
+            slides themselves carry `aria-label="slide N of total"` so a
+            second sr-only mirror would double-announce on every move.
+            The carousel-level region wins because it's tied to the
+            chevron + dot pager via `aria-controls`. */}
         <p id={liveRegionId} aria-live="polite" className="sr-only">
           {t("onboarding.welcome.slideOf", {
             current: active + 1,
@@ -221,11 +223,12 @@ export function WelcomeCarousel() {
         <Button
           type="button"
           variant="ghost"
-          size="icon-sm"
+          size="icon"
           onClick={() => scrollToSlide(Math.max(0, active - 1))}
           disabled={active === 0}
           aria-label={t("onboarding.welcome.prevSlide")}
           aria-controls={liveRegionId}
+          className="min-h-11 min-w-11"
         >
           <ChevronLeft className="size-4" />
         </Button>
@@ -233,7 +236,7 @@ export function WelcomeCarousel() {
         <div
           role="tablist"
           aria-label={t("onboarding.welcome.carouselLabel")}
-          className="flex items-center gap-2"
+          className="flex items-center"
         >
           {SLIDES.map((slide, idx) => (
             <button
@@ -245,24 +248,32 @@ export function WelcomeCarousel() {
                 index: idx + 1,
               })}
               onClick={() => scrollToSlide(idx)}
-              className={cn(
-                "size-2.5 rounded-full transition-colors duration-150 ease-out motion-reduce:transition-none",
-                active === idx ? "bg-primary" : "bg-muted hover:bg-muted-foreground/30",
-              )}
-            />
+              className="inline-flex size-11 items-center justify-center"
+            >
+              <span
+                aria-hidden="true"
+                className={cn(
+                  "size-2.5 rounded-full transition-colors duration-150 ease-out motion-reduce:transition-none",
+                  active === idx
+                    ? "bg-primary"
+                    : "bg-muted hover:bg-muted-foreground/30",
+                )}
+              />
+            </button>
           ))}
         </div>
 
         <Button
           type="button"
           variant="ghost"
-          size="icon-sm"
+          size="icon"
           onClick={() =>
             scrollToSlide(Math.min(SLIDES.length - 1, active + 1))
           }
           disabled={active === SLIDES.length - 1}
           aria-label={t("onboarding.welcome.nextSlide")}
           aria-controls={liveRegionId}
+          className="min-h-11 min-w-11"
         >
           <ChevronRight className="size-4" />
         </Button>
@@ -274,6 +285,7 @@ export function WelcomeCarousel() {
           size="lg"
           onClick={handleGetStarted}
           disabled={advancing}
+          className="min-h-11"
         >
           {t("onboarding.welcome.cta")}
         </Button>