feat: add OPC (One Person Company) management system with Kanban board

Phase 1 MVP implementation:
- PostgreSQL database schema for tasks, agents, executions, time tracking
- Backend API: task CRUD, agent management, automatic time tracking
- Frontend: Kanban board with drag-and-drop (Parking Lot → In Progress → Done)
- Task modal for creating/editing tasks with tags, priority, assignee
- 3 core agents seeded: PM, CTO, COO
- Agent approval workflow: CxO level requires approval, others auto-execute
- Automatic time tracking: starts on in_progress, stops on done
- RBAC integration: OPC page accessible to admin/member roles

Features:
- Drag-and-drop tasks between columns
- Assign tasks to humans or AI agents
- Priority badges (low, medium, high, urgent)
- Tags and due dates
- Task history tracking
- Time entry tracking with automatic timer
- Agent execution records with approval workflow

Next steps:
- Initialize OPC database on NAS
- Implement agent executor service
- Add WebSocket for real-time updates
- Add email notifications
- Add PDF invoice generation

dashboard/frontend/src/lib/opc-api.js

@@ -0,0 +1,80 @@
+/**
+ * OPC API Client
+ */
+import { get, post, put, del } from "./api.js";
+
+// Tasks
+export async function getTasks(filters = {}) {
+  const params = new URLSearchParams();
+  if (filters.status) params.append("status", filters.status);
+  if (filters.assigned_to) params.append("assigned_to", filters.assigned_to);
+  if (filters.project_id) params.append("project_id", filters.project_id);
+  if (filters.priority) params.append("priority", filters.priority);
+  if (filters.tags) params.append("tags", filters.tags.join(","));
+  if (filters.limit) params.append("limit", filters.limit);
+  if (filters.offset) params.append("offset", filters.offset);
+
+  const query = params.toString();
+  return get(`/opc/tasks${query ? "?" + query : ""}`);
+}
+
+export async function createTask(task) {
+  return post("/opc/tasks", task);
+}
+
+export async function updateTask(taskId, updates) {
+  return put(`/opc/tasks/${taskId}`, updates);
+}
+
+export async function deleteTask(taskId) {
+  return del(`/opc/tasks/${taskId}`);
+}
+
+export async function moveTask(taskId, status) {
+  return put(`/opc/tasks/${taskId}/move`, { status });
+}
+
+export async function assignTask(taskId, assigned_to, assigned_type = "human") {
+  return post(`/opc/tasks/${taskId}/assign`, { assigned_to, assigned_type });
+}
+
+export async function getTaskHistory(taskId) {
+  return get(`/opc/tasks/${taskId}/history`);
+}
+
+export async function getTaskTime(taskId) {
+  return get(`/opc/tasks/${taskId}/time`);
+}
+
+// Agents
+export async function getAgents(enabledOnly = true) {
+  return get(`/opc/agents?enabled_only=${enabledOnly}`);
+}
+
+export async function getAgent(agentId) {
+  return get(`/opc/agents/${agentId}`);
+}
+
+export async function triggerAgent(agentId, taskId) {
+  return post(`/opc/agents/${agentId}/execute?task_id=${taskId}`);
+}
+
+// Executions
+export async function getExecutions(filters = {}) {
+  const params = new URLSearchParams();
+  if (filters.task_id) params.append("task_id", filters.task_id);
+  if (filters.agent_id) params.append("agent_id", filters.agent_id);
+  if (filters.status) params.append("status", filters.status);
+  if (filters.limit) params.append("limit", filters.limit);
+
+  const query = params.toString();
+  return get(`/opc/executions${query ? "?" + query : ""}`);
+}
+
+export async function getExecution(executionId) {
+  return get(`/opc/executions/${executionId}`);
+}
+
+export async function approveExecution(executionId, approved) {
+  return post(`/opc/executions/${executionId}/approve`, { approved });
+}