Fix FAB z-index/position, broken image fallbacks, and upload progress UI

- Bug 2: raise all FABs (activity, memories, circle) to z-50 and bottom-24
  so they sit above the bottom nav (z-40, ~56px tall)
- Bug 1: add onError handlers to baby photo (home) and parent avatar (profile)
  so a broken R2 URL shows the 👶 / initials placeholder instead of a broken
  browser icon; reset error flag after a successful upload
- Bug 3: replace ⏳ emoji spinner with a proper CSS spinner on home page baby
  photo; add a fixed upload-progress toast to the memories page that appears
  at the top of the screen for the full duration of the upload

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

src/app/(app)/activity/page.tsx

@@ -371,7 +371,7 @@ export default function ActivityPage() {
       </div>
 
       {/* FAB */}
-      <div className="fixed bottom-20 right-5 flex flex-col items-end gap-2 z-40">
+      <div className="fixed bottom-24 right-5 flex flex-col items-end gap-2 z-50">
         {fabOpen && (["feed", "sleep", "diaper"] as ModalLogType[]).map(t => (
           <button
             key={t}

src/app/(app)/circle/[id]/page.tsx

@@ -615,7 +615,7 @@ export default function CircleFeedPage({ params }: { params: Promise<{ id: strin
       {/* FAB — create post */}
       <button
         onClick={() => setShowCreate(true)}
-        className="fixed bottom-20 right-5 w-14 h-14 bg-rose-400 text-white rounded-full shadow-lg flex items-center justify-center text-2xl z-40"
+        className="fixed bottom-24 right-5 w-14 h-14 bg-rose-400 text-white rounded-full shadow-lg flex items-center justify-center text-2xl z-50"
       >+</button>
 
       {showCreate && circle && familyId && (

src/app/(app)/home/page.tsx

@@ -89,6 +89,7 @@ export default function HomePage() {
   const [vaccineReminders, setVaccineReminders] = useState<any[]>([]);
   const [aiChips, setAiChips] = useState<string[]>([]);
   const [uploadingPhoto, setUploadingPhoto] = useState(false);
+  const [photoError, setPhotoError] = useState(false);
   const [showPhotoMenu, setShowPhotoMenu] = useState(false);
   const photoInputRef = useRef<HTMLInputElement>(null);
   const { theme, toggle: toggleTheme } = useTheme();
@@ -215,6 +216,7 @@ export default function HomePage() {
       });
 
       // 4. Update in-memory state immediately — no full reload needed
+      setPhotoError(false);
       updateChildImage(childId, publicUrl);
     } catch (err) {
       console.error("Photo upload failed:", err);
@@ -318,15 +320,18 @@ export default function HomePage() {
             className="relative group"
             title={child?.imageUrl ? "Photo options" : "Add photo"}
           >
-            {child?.imageUrl
-              ? <img src={child.imageUrl} alt={child?.name} className="w-16 h-16 rounded-full object-cover" />
+            {child?.imageUrl && !photoError
+              ? <img src={child.imageUrl} alt={child?.name} className="w-16 h-16 rounded-full object-cover" onError={() => setPhotoError(true)} />
               : <div className="w-16 h-16 bg-rose-100 dark:bg-rose-900 rounded-full flex items-center justify-center text-2xl">👶</div>
             }
-            {/* Camera overlay */}
+            {/* Camera / upload overlay */}
             <div className={`absolute inset-0 rounded-full flex items-center justify-center transition-opacity ${
               uploadingPhoto ? "bg-black/40 opacity-100" : "bg-black/0 opacity-0 group-hover:opacity-100 group-active:opacity-100"
             }`}>
-              <span className="text-white text-lg">{uploadingPhoto ? "⏳" : "📷"}</span>
+              {uploadingPhoto
+                ? <div className="w-6 h-6 border-2 border-white border-t-transparent rounded-full animate-spin" />
+                : <span className="text-white text-lg">📷</span>
+              }
             </div>
           </button>
 

src/app/(app)/memories/page.tsx

@@ -351,8 +351,16 @@ export default function MemoriesPage() {
         </div>
       </div>
 
+      {/* Upload progress toast */}
+      {uploading && (
+        <div className="fixed top-4 inset-x-4 z-50 bg-gray-900/90 text-white text-sm rounded-2xl px-4 py-3 flex items-center gap-3 shadow-xl pointer-events-none">
+          <div className="w-5 h-5 border-2 border-white border-t-transparent rounded-full animate-spin flex-shrink-0" />
+          <span>Uploading photo…</span>
+        </div>
+      )}
+
       {/* Upload FAB — disabled when storage quota is exceeded */}
-      <div className="fixed bottom-6 right-6 z-20">
+      <div className="fixed bottom-24 right-6 z-50">
         <button
           onClick={quotaExceeded ? undefined : handleUploadClick}
           disabled={uploading || quotaExceeded}

src/app/(app)/profile/page.tsx

@@ -15,6 +15,7 @@ export default function ProfilePage() {
   const [saving, setSaving]       = useState(false);
   const [uploading, setUploading] = useState(false);
   const [saveMsg, setSaveMsg]     = useState("");
+  const [avatarError, setAvatarError] = useState(false);
 
   useEffect(() => {
     fetch("/api/auth/profile")
@@ -67,6 +68,7 @@ export default function ProfilePage() {
       if (!patchRes.ok) throw new Error(patchData.error || "Failed to save photo");
 
       setAvatarUrl(newPublicUrl);
+      setAvatarError(false);
       setSaveMsg("Photo updated!");
     } catch (err) {
       setSaveMsg(err instanceof Error ? err.message : "Upload failed");
@@ -125,11 +127,12 @@ export default function ProfilePage() {
         {/* Avatar */}
         <div className="flex flex-col items-center pt-8 pb-4">
           <div className="relative mb-3">
-            {avatarUrl ? (
+            {avatarUrl && !avatarError ? (
               <img
                 src={avatarUrl}
                 alt={name}
                 className="w-24 h-24 rounded-full object-cover ring-4 ring-white dark:ring-gray-800 shadow-md"
+                onError={() => setAvatarError(true)}
               />
             ) : (
               <div className="w-24 h-24 rounded-full bg-gradient-to-br from-rose-300 to-amber-300 flex items-center justify-center text-white text-2xl font-bold shadow-md ring-4 ring-white dark:ring-gray-800">