Add Paginated GET /api/documents Endpoint with Filters for Status, Risk Score, Date Range, and Title Search

[mftee]

Description:
Add a paginated search and filtering endpoint as an independent query feature so users can query their uploaded documents by status, risk score, date range, and keyword.

Tasks:

• Implement GET /api/documents with query params: status, min_risk_score, max_risk_score, from_date, to_date, search (matches document title), page, limit
• Use TypeORM QueryBuilder to construct the dynamic query
• Return: { data: DocumentDto[], total: number, page: number, limit: number }
• Regular users see only their own documents; admin users see all documents
• Protect the route with JwtAuthGuard

Acceptance Criteria:

• All filter params are optional and combinable
• Pagination defaults to page=1, limit=20, max limit=100
• The search param performs a case-insensitive partial match on title
• Admin users can see documents belonging to any user