tasks: shared task board with sticker rewards, difficulty levels, and calendar

Complete household task management system behind task_users auth group:
- Task CRUD with recurring schedules, assignees, tags, and optional difficulty
- Blobcat SVG sticker rewards on completion, rarity weighted by difficulty
- Sticker collection page with calendar view and progress tracking
- Redesigned cards with left accent urgency strip, assignee PFP, round check button
- Weekday-based due date labels for tasks within 7 days
- Tasks link added to homepage LinksGrid

src/routes/api/tasks/+server.ts

@@ -0,0 +1,46 @@
+import type { RequestHandler } from '@sveltejs/kit';
+import { Task } from '$models/Task';
+import { dbConnect } from '$utils/db';
+import { error, json } from '@sveltejs/kit';
+
+export const GET: RequestHandler = async ({ locals }) => {
+  const auth = await locals.auth();
+  if (!auth?.user?.nickname) throw error(401, 'Not logged in');
+
+  await dbConnect();
+
+  const tasks = await Task.find({ active: true })
+    .sort({ nextDueDate: 1 })
+    .lean();
+
+  return json({ tasks });
+};
+
+export const POST: RequestHandler = async ({ request, locals }) => {
+  const auth = await locals.auth();
+  if (!auth?.user?.nickname) throw error(401, 'Not logged in');
+
+  const data = await request.json();
+  const { title, description, assignees, tags, difficulty, isRecurring, frequency, nextDueDate } = data;
+
+  if (!title?.trim()) throw error(400, 'Title is required');
+  if (!nextDueDate) throw error(400, 'Due date is required');
+  if (isRecurring && !frequency?.type) throw error(400, 'Frequency is required for recurring tasks');
+
+  await dbConnect();
+
+  const task = await Task.create({
+    title: title.trim(),
+    description: description?.trim(),
+    assignees: assignees || [],
+    tags: tags || [],
+    difficulty: difficulty || undefined,
+    isRecurring: !!isRecurring,
+    frequency: isRecurring ? frequency : undefined,
+    nextDueDate: new Date(nextDueDate),
+    createdBy: auth.user.nickname,
+    active: true
+  });
+
+  return json({ task }, { status: 201 });
+};