fix: unify theme system - fix theme switching persistence

- Unified localStorage key to 'theme-preference' across all components
- Fixed header.tsx using wrong localStorage key ('theme' instead of 'theme-preference')
- Added localStorage hybrid persistence for instant theme changes
- Removed router.refresh() which was causing stale data revert
- Replaced Blue theme with Sepia
- Consolidated auth() calls to prevent race conditions
- Updated UserSettingsData types to include all themes

keep-notes/app/actions/profile.ts

@@ -146,7 +146,7 @@ export async function updateFontSize(fontSize: string) {
         where: { userId: session.user.id },
         data: { fontSize: fontSize }
       })
-      } else {
+    } else {
       // Create new with all required fields
       result = await prisma.userAISettings.create({
         data: {
@@ -163,7 +163,7 @@ export async function updateFontSize(fontSize: string) {
           showRecentNotes: false
         }
       })
-      }
+    }
 
     revalidatePath('/')
     revalidatePath('/settings/profile')
@@ -179,49 +179,18 @@ export async function updateShowRecentNotes(showRecentNotes: boolean) {
   if (!session?.user?.id) return { error: 'Unauthorized' }
 
   try {
-    // Use EXACT same pattern as updateFontSize which works
-    const existing = await prisma.userAISettings.findUnique({
-      where: { userId: session.user.id }
+    await prisma.userAISettings.upsert({
+      where: { userId: session.user.id },
+      create: {
+        userId: session.user.id,
+        showRecentNotes,
+        // Defaults will be used for other fields
+      },
+      update: {
+        showRecentNotes,
+      },
     })
 
-    if (existing) {
-      // Try Prisma client first, fallback to raw SQL if field doesn't exist in client
-      try {
-        await prisma.userAISettings.update({
-          where: { userId: session.user.id },
-          data: { showRecentNotes: showRecentNotes } as any
-        })
-      } catch (prismaError: any) {
-        // If Prisma client doesn't know about showRecentNotes, use raw SQL
-        if (prismaError?.message?.includes('Unknown argument') || prismaError?.code === 'P2009') {
-          const value = showRecentNotes ? 1 : 0
-          await prisma.$executeRaw`
-            UPDATE UserAISettings 
-            SET showRecentNotes = ${value}
-            WHERE userId = ${session.user.id}
-          `
-        } else {
-          throw prismaError
-        }
-      }
-    } else {
-      // Create new - same as updateFontSize
-      await prisma.userAISettings.create({
-        data: {
-          userId: session.user.id,
-          titleSuggestions: true,
-          semanticSearch: true,
-          paragraphRefactor: true,
-          memoryEcho: true,
-          memoryEchoFrequency: 'daily',
-          aiProvider: 'auto',
-          preferredLanguage: 'auto',
-          fontSize: 'medium',
-          showRecentNotes: showRecentNotes
-        } as any
-      })
-    }
-
     revalidatePath('/')
     revalidatePath('/settings/profile')
     return { success: true, showRecentNotes }