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/models/Task.ts

@@ -0,0 +1,92 @@
+import mongoose from 'mongoose';
+
+export interface ITask {
+  _id?: string;
+  title: string;
+  description?: string;
+  assignees: string[];
+  tags: string[];
+  difficulty?: 'low' | 'medium' | 'high';
+  isRecurring: boolean;
+  frequency?: {
+    type: 'daily' | 'weekly' | 'biweekly' | 'monthly' | 'custom';
+    customDays?: number;
+  };
+  nextDueDate: Date;
+  lastCompletedAt?: Date;
+  lastCompletedBy?: string;
+  createdBy: string;
+  active: boolean;
+  createdAt?: Date;
+  updatedAt?: Date;
+}
+
+const TaskSchema = new mongoose.Schema(
+  {
+    title: {
+      type: String,
+      required: true,
+      trim: true
+    },
+    description: {
+      type: String,
+      trim: true
+    },
+    assignees: [{
+      type: String,
+      trim: true
+    }],
+    tags: [{
+      type: String,
+      trim: true,
+      lowercase: true
+    }],
+    difficulty: {
+      type: String,
+      enum: ['low', 'medium', 'high']
+    },
+    isRecurring: {
+      type: Boolean,
+      required: true,
+      default: false
+    },
+    frequency: {
+      type: {
+        type: String,
+        enum: ['daily', 'weekly', 'biweekly', 'monthly', 'custom']
+      },
+      customDays: {
+        type: Number,
+        min: 1
+      }
+    },
+    nextDueDate: {
+      type: Date,
+      required: true
+    },
+    lastCompletedAt: {
+      type: Date
+    },
+    lastCompletedBy: {
+      type: String,
+      trim: true
+    },
+    createdBy: {
+      type: String,
+      required: true,
+      trim: true
+    },
+    active: {
+      type: Boolean,
+      default: true
+    }
+  },
+  {
+    timestamps: true
+  }
+);
+
+TaskSchema.index({ active: 1, nextDueDate: 1 });
+TaskSchema.index({ tags: 1 });
+
+export const Task = mongoose.model<ITask>('Task', TaskSchema);

src/models/TaskCompletion.ts

@@ -0,0 +1,51 @@
+import mongoose from 'mongoose';
+
+export interface ITaskCompletion {
+  _id?: string;
+  taskId: mongoose.Types.ObjectId;
+  taskTitle: string;
+  completedBy: string;
+  completedAt: Date;
+  stickerId?: string;
+  tags: string[];
+}
+
+const TaskCompletionSchema = new mongoose.Schema(
+  {
+    taskId: {
+      type: mongoose.Schema.Types.ObjectId,
+      ref: 'Task',
+      required: true
+    },
+    taskTitle: {
+      type: String,
+      required: true,
+      trim: true
+    },
+    completedBy: {
+      type: String,
+      required: true,
+      trim: true
+    },
+    completedAt: {
+      type: Date,
+      required: true,
+      default: Date.now
+    },
+    stickerId: {
+      type: String,
+      trim: true
+    },
+    tags: [{
+      type: String,
+      trim: true,
+      lowercase: true
+    }]
+  }
+);
+
+TaskCompletionSchema.index({ completedBy: 1 });
+TaskCompletionSchema.index({ taskId: 1 });
+TaskCompletionSchema.index({ completedAt: -1 });
+
+export const TaskCompletion = mongoose.model<ITaskCompletion>('TaskCompletion', TaskCompletionSchema);