Simplify hero backgrounds and add entrance animations

- Replace animated blob/wave/noise backdrop with clean static gradient
  (radial ellipse highlights + linear fade) in hero-motion-backdrop
- Remove all framer-motion from background layer; delete unused CSS
  classes: hero-blob, hero-sheet-glow, hero-sheet-wave, hero-sheet-noise,
  hero-title-shift keyframe, and responsive blob media queries
- Add framer-motion stagger entrance to HeroContentMotion, HeroMotionItem,
  and HeroTitle (slide-up + fade on mount)
- Refactor coming-soon page to use HeroContentMotion/HeroMotionItem
  instead of MotionFade (whileInView unreliable above the fold)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

components/layout/page-hero.tsx

@@ -3,7 +3,7 @@ import { HeroContentMotion, HeroMotionItem, HeroShell, HeroTitle, type HeroTitle
 
 type PageHeroProps = {
   badge?: string;
-  title: string;
+  title?: string;
   description?: string;
   lines?: HeroTitleLineValue[];
   locale?: string;
@@ -33,13 +33,19 @@ function getDefaultLines(title: string): HeroTitleLineValue[] {
 }
 
 export function PageHero({ badge, title, description, lines, locale }: PageHeroProps) {
+  const resolvedLines = lines ?? (title ? getDefaultLines(title) : undefined);
+
   return (
     <HeroShell compactBackdrop variant="page">
       <HeroContentMotion variant="page">
-        <HeroMotionItem variant="page">
-          <HeroBadge>{badge ?? title}</HeroBadge>
-        </HeroMotionItem>
-        <HeroTitle lines={lines ?? getDefaultLines(title)} locale={locale} variant="page" />
+        {(badge ?? title) ? (
+          <HeroMotionItem variant="page">
+            <HeroBadge>{badge ?? title}</HeroBadge>
+          </HeroMotionItem>
+        ) : null}
+        {resolvedLines ? (
+          <HeroTitle lines={resolvedLines} locale={locale} variant="page" />
+        ) : null}
         {description ? (
           <HeroMotionItem variant="page">
             <p className="mx-auto mt-6 max-w-[34rem] text-base leading-7 text-foreground/72">