feat: add image selection to Assets step and remove duplicate media library

apps/admin/src/components/EditorShell.tsx

@@ -226,6 +226,8 @@ export default function EditorShell({ onLogout, initialPostId, onBack }: { onLog
                   }
                 }}
                 onSetFeature={(url: string) => setMeta(m => ({ ...m, featureImage: url }))}
+                selectedKeys={genImageKeys}
+                onToggleSelect={toggleGenImage}
               />
             </StepContainer>
           )}

apps/admin/src/components/MediaLibrary.tsx

@@ -131,8 +131,7 @@ export default function MediaLibrary({
 
   return (
     <Paper sx={{ p: 2 }}>
-      <Stack direction="row" justifyContent="space-between" alignItems="center" sx={{ mb: 2 }}>
-        <Typography variant="h6">Media Library</Typography>
+      <Stack direction="row" justifyContent="flex-end" alignItems="center" sx={{ mb: 2 }}>
         <Stack direction="row" spacing={1} alignItems="center">
           <TextField
             size="small"

apps/admin/src/components/steps/StepAssets.tsx

@@ -10,12 +10,16 @@ export default function StepAssets({
   onInsertAtCursor,
   onInsertImage,
   onSetFeature,
+  selectedKeys,
+  onToggleSelect,
 }: {
   draftId?: string | null;
   postClips: Clip[];
   onInsertAtCursor: (html: string) => void;
   onInsertImage: (url: string) => void;
   onSetFeature: (url: string) => void;
+  selectedKeys?: string[];
+  onToggleSelect?: (key: string) => void;
 }) {
   return (
     <Box sx={{ display: 'grid', gap: 2 }}>
@@ -33,6 +37,9 @@ export default function StepAssets({
             onInsert={onInsertImage}
             onSetFeature={onSetFeature}
             showSetFeature
+            selectionMode
+            selectedKeys={selectedKeys}
+            onToggleSelect={onToggleSelect}
           />
         </Box>
       </Stack>

apps/admin/src/components/steps/StepGenerate.tsx

@@ -1,5 +1,4 @@
 import { Box, Stack, TextField, Typography } from '@mui/material';
-import MediaLibrary from '../MediaLibrary';
 import SelectedImages from './SelectedImages';
 import CollapsibleSection from './CollapsibleSection';
 import type { Clip } from './StepAssets';
@@ -46,10 +45,7 @@ export default function StepGenerate({
         <SelectedImages imageKeys={genImageKeys} onRemove={onToggleGenImage} />
       </CollapsibleSection>
 
-      {/* Media library */}
-      <CollapsibleSection title="Media Library">
-        <MediaLibrary selectionMode selectedKeys={genImageKeys} onToggleSelect={onToggleGenImage} />
-      </CollapsibleSection>
+      {/* Media library removed: selection now happens in Assets step */}
 
       {/* Prompt */}
       <CollapsibleSection title="AI Prompt">