fix(reader): grey out share/permissions and other live-only actions offline

Share, Permissions, Templatize, Duplicate, Unpublish, Archive, Move,
New Document, History, Insights (sheet + Viewer Insights toggle), and
Download all hit the server directly with no offline path — disabled
(with a tooltip on the two toolbar buttons) whenever the app isn't
effectively online, instead of failing confusingly on tap.

Left enabled: Edit, Pin/Unpin, Star/Unstar, Subscribed, Full Width
(all queue via CachingOutlineAPIClient and sync later), Present and
Search in Document (both read documents.info, which is cached), and
Copy/Print (read already-loaded text directly, no network at all).

Outpost/Features/Collections/DocumentReaderView.swift

@@ -12,6 +12,7 @@ import OutlineKit
 struct DocumentReaderView: View {
     @Environment(SessionStore.self) private var session
     @Environment(StarStore.self) private var starStore
+    @AppStorage(CachingOutlineAPIClient.offlineModeDefaultsKey) private var isOfflineModeEnabled = false
 
     @State private var viewModel: DocumentReaderViewModel
     let apiClient: OutlineAPIClient
@@ -56,6 +57,15 @@ struct DocumentReaderView: View {
         self.onDocumentCreated = onDocumentCreated
     }
 
+    /// Editing, pin/star/subscribe, and Full Width all queue and sync later
+    /// (see `CachingOutlineAPIClient`) — everything else here (sharing,
+    /// permissions, move/archive/delete/duplicate/templatize, history,
+    /// insights, export) hits the server directly with no offline path, so
+    /// it's disabled rather than left to fail confusingly on tap.
+    private var isEffectivelyOnline: Bool {
+        session.networkMonitor.isOnline && !isOfflineModeEnabled
+    }
+
     var body: some View {
         ScrollView {
             VStack(alignment: .leading, spacing: 12) {
@@ -110,7 +120,8 @@ struct DocumentReaderView: View {
                 } label: {
                     Image(systemName: "square.and.arrow.up")
                 }
-                .help("Share")
+                .help(isEffectivelyOnline ? "Share" : "Sharing needs an internet connection")
+                .disabled(!isEffectivelyOnline)
                 .popover(isPresented: $isShowingShareSheet, arrowEdge: .bottom) {
                     DocumentShareSheet(apiClient: apiClient, documentId: viewModel.documentId)
                 }
@@ -131,7 +142,8 @@ struct DocumentReaderView: View {
                 } label: {
                     Image(systemName: "doc.badge.plus")
                 }
-                .help("New Document")
+                .help(isEffectivelyOnline ? "New Document" : "Creating documents needs an internet connection")
+                .disabled(!isEffectivelyOnline)
 
                 Menu {
                     menuContent
@@ -235,7 +247,8 @@ struct DocumentReaderView: View {
             viewModel.isPinned,
             viewModel.isInsightsEnabled ?? false,
             viewModel.isFullWidth,
-            viewModel.isEditing
+            viewModel.isEditing,
+            isEffectivelyOnline
         ].map(String.init).joined(separator: "-")
     }
 
@@ -305,27 +318,33 @@ struct DocumentReaderView: View {
         Button("Permissions…") {
             isShowingShareSheet = true
         }
+        .disabled(!isEffectivelyOnline)
 
         Divider()
 
         Button("Templatize") {
             Task { await templatize() }
         }
+        .disabled(!isEffectivelyOnline)
         Button("Duplicate") {
             Task { await duplicate() }
         }
+        .disabled(!isEffectivelyOnline)
         Button("Unpublish") {
             isShowingUnpublishConfirmation = true
         }
+        .disabled(!isEffectivelyOnline)
         Button("Archive…") {
             isShowingArchiveConfirmation = true
         }
+        .disabled(!isEffectivelyOnline)
 
         Divider()
 
         Button("Move") {
             isShowingMoveSheet = true
         }
+        .disabled(!isEffectivelyOnline)
         // Multipart file upload is its own subsystem — deferred rather than
         // half-built here.
         Button("Import Document…") {}
@@ -333,6 +352,7 @@ struct DocumentReaderView: View {
         Button("New Document") {
             isShowingNewDocumentSheet = true
         }
+        .disabled(!isEffectivelyOnline)
         Button(viewModel.isPinned ? "Unpin from Home" : "Pin to Home") {
             Task { await togglePin() }
         }
@@ -342,9 +362,13 @@ struct DocumentReaderView: View {
         Button("History") {
             isShowingHistorySheet = true
         }
+        .disabled(!isEffectivelyOnline)
         Button("Insights") {
             isShowingInsightsSheet = true
         }
+        .disabled(!isEffectivelyOnline)
+        // Present/Search in Document both read `documents.info`, which is
+        // read-through cached — they work offline on whatever's cached.
         Button("Present") {
             isShowingPresentSheet = true
         }
@@ -354,6 +378,7 @@ struct DocumentReaderView: View {
         Button("Download") {
             Task { await download() }
         }
+        .disabled(!isEffectivelyOnline)
         Button("Copy") {
             Task { await copyMarkdown() }
         }
@@ -370,6 +395,7 @@ struct DocumentReaderView: View {
             get: { viewModel.isInsightsEnabled ?? false },
             set: { _ in Task { await toggleInsights() } }
         ))
+        .disabled(!isEffectivelyOnline)
         // Confirmed against a live server: there's no per-document embeds
         // field. Only a workspace-level setting exists, and that's not
         // reachable via the API either (no `team.update` endpoint in the
@@ -386,6 +412,7 @@ struct DocumentReaderView: View {
         Button("Delete…", role: .destructive) {
             isShowingDeleteConfirmation = true
         }
+        .disabled(!isEffectivelyOnline)
     }
 
     private func star() async {