perf: slim entries API + on-demand article loading for iOS Reader

Server: add slim query param (default true) to entries list endpoint,
returning EntrySlimOut without content/full_content HTML — cuts payload
size dramatically for list views. Single entry endpoint still returns
full content.

iOS: ArticleView now fetches full entry content on demand when opened
instead of relying on list data. Shows loading indicator while fetching.
Mark-as-read is fire-and-forget to avoid blocking the view.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ios/Platform/Platform/Features/Reader/Views/ArticleView.swift

@@ -7,6 +7,8 @@ struct ArticleView: View {
     @State private var isFetchingFull = false
     @State private var savedToBrain = false
     @State private var webViewHeight: CGFloat = 400
+    @State private var isContentReady = false
+    @State private var articleContent = ""
 
     init(entry: ReaderEntry, vm: ReaderViewModel) {
         self.entry = entry
@@ -53,7 +55,17 @@ struct ArticleView: View {
                     .padding(.horizontal, 16)
 
                 // Article body
-                if currentEntry.articleHTML.isEmpty {
+                if !isContentReady {
+                    HStack {
+                        ProgressView()
+                            .controlSize(.small)
+                        Text("Loading article...")
+                            .font(.caption)
+                            .foregroundStyle(Color.textTertiary)
+                    }
+                    .frame(maxWidth: .infinity)
+                    .padding(.vertical, 40)
+                } else if articleContent.isEmpty {
                     if isFetchingFull {
                         HStack {
                             ProgressView()
@@ -82,7 +94,7 @@ struct ArticleView: View {
                         .padding(.vertical, 40)
                     }
                 } else {
-                    ArticleWebView(html: wrapHTML(currentEntry.articleHTML), contentHeight: $webViewHeight)
+                    ArticleWebView(html: wrapHTML(articleContent), contentHeight: $webViewHeight)
                         .frame(height: webViewHeight)
                 }
 
@@ -142,8 +154,22 @@ struct ArticleView: View {
             }
         }
         .task {
-            // Auto-mark as read
-            await vm.markAsRead(entry)
+            // Auto-mark as read (fire-and-forget)
+            Task { await vm.markAsRead(entry) }
+
+            // Fetch full entry content on demand
+            do {
+                let fullEntry = try await ReaderAPI().getEntry(id: currentEntry.id)
+                currentEntry = fullEntry
+                articleContent = fullEntry.articleHTML
+                if let idx = vm.entries.firstIndex(where: { $0.id == fullEntry.id }) {
+                    vm.entries[idx] = fullEntry
+                }
+            } catch {
+                // Fall back to whatever content we already have
+                articleContent = currentEntry.articleHTML
+            }
+            isContentReady = true
         }
     }
 
@@ -166,6 +192,7 @@ struct ArticleView: View {
         do {
             let updated = try await ReaderAPI().fetchFullContent(entryId: currentEntry.id)
             currentEntry = updated
+            articleContent = updated.articleHTML
             if let idx = vm.entries.firstIndex(where: { $0.id == updated.id }) {
                 vm.entries[idx] = updated
             }