UX: Update Thinker module pages with user-friendly text

- Prompts: Changed 'AI Prompts Management' to 'Prompt Library'
- Author Profiles: Changed to 'Writing Styles'
- Strategies: Changed 'Content Strategies' to 'Content Plans'
- Image Testing: Changed to 'Image Settings'
- Dashboard: Changed 'Thinker Dashboard' to 'Strategy Dashboard'

frontend/src/pages/Thinker/Prompts.tsx

@@ -209,9 +209,9 @@ export default function Prompts() {
 
   return (
     <>
-      <PageMeta title="Prompts - IGNY8" description="AI prompts management" />
+      <PageMeta title="Prompt Library - IGNY8" description="Manage your AI writing prompts" />
       <PageHeader 
-        title="AI Prompts Management" 
+        title="Prompt Library" 
         badge={{ icon: <BoltIcon />, color: 'orange' }}
         navigation={<ModuleNavigationTabs tabs={thinkerTabs} />}
       />