EAS build config + Collaboration UI + i18n updates

- eas.json for Android APK/AAB + iOS builds
- Collaboration page: assign, transfer, claim, subtasks
- Task detail: assignee avatars, subtask progress
- Updated translations (cs,he,ru,ua)

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

apps/tasks/lib/api.ts

@@ -245,3 +245,61 @@ export function deleteProject(token: string, id: string) {
 export function inviteToProject(token: string, id: string, userId: string) {
   return apiFetch<{ data: Project; status: string }>("/api/v1/projects/" + id + "/invite", { method: "POST", body: { user_id: userId }, token });
 }
+
+// Subtasks
+export interface Subtask {
+  id: string;
+  parent_task_id: string;
+  title: string;
+  description: string;
+  status: "pending" | "in_progress" | "done" | "completed";
+  assigned_to: string | null;
+  assignee_name: string | null;
+  order_index: number;
+  completed_at: string | null;
+  created_at: string;
+  updated_at: string;
+}
+
+export interface CollabRequest {
+  id: string;
+  task_id: string;
+  from_user_id: string | null;
+  to_user_id: string;
+  type: "assign" | "transfer" | "collaborate" | "claim";
+  status: "pending" | "accepted" | "rejected";
+  message: string;
+  from_name: string | null;
+  to_name: string | null;
+  task_title?: string;
+  created_at: string;
+  responded_at: string | null;
+}
+
+export function getSubtasks(token: string, taskId: string) {
+  return apiFetch<{ data: Subtask[] }>(`/api/v1/tasks/${taskId}/subtasks`, { token });
+}
+
+export function createSubtask(token: string, taskId: string, data: { title: string; description?: string; assigned_to?: string }) {
+  return apiFetch<{ data: Subtask }>(`/api/v1/tasks/${taskId}/subtasks`, { method: "POST", body: data, token });
+}
+
+export function updateSubtask(token: string, taskId: string, subtaskId: string, data: Partial<Subtask>) {
+  return apiFetch<{ data: Subtask }>(`/api/v1/tasks/${taskId}/subtasks/${subtaskId}`, { method: "PUT", body: data, token });
+}
+
+export function deleteSubtask(token: string, taskId: string, subtaskId: string) {
+  return apiFetch<void>(`/api/v1/tasks/${taskId}/subtasks/${subtaskId}`, { method: "DELETE", token });
+}
+
+export function getCollaborationHistory(token: string, taskId: string) {
+  return apiFetch<{ data: CollabRequest[] }>(`/api/v1/tasks/${taskId}/collaboration`, { token });
+}
+
+export function sendCollabRequest(token: string, taskId: string, data: { to_user_id?: string; from_user_id?: string; type: string; message?: string }) {
+  return apiFetch<{ data?: CollabRequest; status: string }>(`/api/v1/tasks/${taskId}/collaborate`, { method: "POST", body: data, token });
+}
+
+export function searchUsers(token: string, query: string) {
+  return apiFetch<{ data: { id: string; name: string; email: string; avatar_url: string | null }[] }>(`/api/v1/auth/users/search?q=${encodeURIComponent(query)}`, { token });
+}