fix: load tasks via TasksApi in Knowledge view, remove tab counts

Tasks are not part of the knowledge API (backend rejects type=task).
When the Tasks tab is selected, fetch from /api/tasks and convert to
KnowledgeItem. Also removes per-type counts from tab labels to prevent
tabs from awkwardly resizing when counts load.

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

lib/providers/knowledge_provider.dart

@@ -4,6 +4,8 @@ import '../data/models/knowledge_item.dart';
 import '../data/repositories/knowledge_repository.dart';
 import 'api_client_provider.dart';
 
+export '../data/models/knowledge_item.dart';
+
 /// Immutable state for the Knowledge screen's two-tier paginated feed.
 class KnowledgeState {
   final List<int> ids;
@@ -150,6 +152,23 @@ class KnowledgeNotifier extends Notifier<KnowledgeState> {
   Future<void> _fetchFromScratch() async {
     state = state.copyWith(isLoadingIds: true, error: null);
     try {
+      if (state.noteType == 'task') {
+        // Tasks live under /api/tasks — fetch all and convert directly.
+        final tasks = await ref.read(tasksApiProvider).getAll();
+        final items = {
+          for (final t in tasks) t.id: KnowledgeItem.fromTask(t),
+        };
+        state = state.copyWith(
+          ids: tasks.map((t) => t.id).toList(),
+          items: items,
+          totalIds: tasks.length,
+          isLoadingIds: false,
+          hasMore: false,
+        );
+        await _loadCounts();
+        return;
+      }
+
       final (ids, total) = await _repo.fetchIds(
         noteType: state.noteType,
         tags: state.activeTags,