Implement Pagination and Filtering Utility Module

[Mkalbani]

Description

Create a shared common utility module that provides reusable pagination, filtering, and sorting helpers. Rather than each module implementing its own pagination logic inconsistently, a centralised utility ensures uniform API behaviour, consistent response shapes, and less duplicated code. This will be imported by puzzles, leaderboard, users, and sessions modules.

Acceptance Criteria

• A common module is scaffolded at src/common/
• A PaginationDto class provides page, limit, and optional sortBy/order fields
• A paginate() utility wraps TypeORM queries and returns { data, total, page, limit, totalPages }
• A FilterDto base class supports search and date range fields (from, to)
• All paginated endpoints in other modules use these shared utilities
• page defaults to 1 and limit defaults to 20 with a max of 100
• Unit tests cover pagination math, empty results, and limit clamping