feat(content): add places, code mode, mobile context tab, and detail views

- Add Places/Restaurants content type with PlaceCard, PlaceDetail, PlaceGrid
- Add WebsiteDetail and MagazineSectionDetail views for Context panel
- Enhance MagazineGrid hero with background image and 3x taller header
- Add mobile 3-tab layout (Chat, Content, Context) with detail navigation
- Add /code command system: useCodeContext composable, ProjectGrid, FileTreeNode,
  CodeDetail for IDE-style code viewing across all three panels
- Fix /code bubble and prompt index clicks to re-activate code mode
- Fix updatePanelFromText overwriting code tab by skipping command messages

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

packages/app/src/components/content/DetailView.vue

@@ -29,11 +29,33 @@
     :image="selectedImage"
     @back="closeImageDetail"
   />
+  <PlaceDetail
+    v-else-if="selectedPlace"
+    :place="selectedPlace"
+    @back="closePlaceDetail"
+  />
   <ArticleDetail
     v-else-if="selectedArticle"
     :article="selectedArticle"
     @back="closeArticleDetail"
   />
+  <WebsiteDetail
+    v-else-if="selectedWebsite"
+    :website="selectedWebsite"
+    @back="closeWebsiteDetail"
+  />
+  <MagazineSectionDetail
+    v-else-if="selectedMagazineSection"
+    :section="selectedMagazineSection"
+    :current-index="magazineSectionIndex"
+    :total-sections="panelMagazineSections.length"
+    @back="closeMagazineSectionDetail"
+    @navigate="navigateMagazineSection"
+  />
+  <CodeDetail
+    v-else-if="isCodeMode && activeCodeFile"
+    @back="closeCodeFile"
+  />
 </template>
 
 <script setup lang="ts">
@@ -44,13 +66,27 @@ import TVSeriesDetail from './TVSeriesDetail.vue'
 import SongDetail from './SongDetail.vue'
 import PodcastDetail from './PodcastDetail.vue'
 import ImageDetail from './ImageDetail.vue'
+import PlaceDetail from './PlaceDetail.vue'
 import ArticleDetail from './ArticleDetail.vue'
+import WebsiteDetail from './WebsiteDetail.vue'
+import MagazineSectionDetail from './MagazineSectionDetail.vue'
+import CodeDetail from './CodeDetail.vue'
+import { useCodeContext } from '@/composables/useCodeContext'
+
+const { isCodeMode, activeFile: activeCodeFile } = useCodeContext()
+
+function closeCodeFile() {
+  const { activeFile, activeFileContent } = useCodeContext()
+  activeFile.value = null
+  activeFileContent.value = ''
+}
 
 const {
   selectedFilm,
   selectedBook,
   selectedTVSeries,
   selectedImage,
+  selectedPlace,
   selectedSong,
   selectedPodcast,
   selectedArticle,
@@ -58,8 +94,16 @@ const {
   closeBookDetail,
   closeTVSeriesDetail,
   closeImageDetail,
+  closePlaceDetail,
   closeSongDetail,
   closePodcastDetail,
   closeArticleDetail,
+  selectedWebsite,
+  closeWebsiteDetail,
+  selectedMagazineSection,
+  magazineSectionIndex,
+  panelMagazineSections,
+  closeMagazineSectionDetail,
+  navigateMagazineSection,
 } = useContentPanel()
 </script>