Feature: Document Management Library

[avikeid2007]

Summary

Extend the existing RAG document support into a full Document Management Library - upload, organize, tag, and search documents persistently. Documents can be used as context for any chat.

Motivation

Currently documents are used per-RAG-session. A persistent document library lets users build a personal knowledge base.

Detailed Requirements

Enhancements to existing DocumentView.xaml

• Add folder/category organization (tree view or flat categories)
• Tag documents with custom labels
• Full-text search across all indexed documents
• Document preview panel (show first N lines or summary)
• Bulk operations (select multiple, delete, re-index)
• "Chat with this document" quick action -> opens chat with RAG context pre-loaded

Database Changes (DatabaseService.cs)

Add DocumentLibrary table:

CREATE TABLE IF NOT EXISTS DocumentLibrary (
    Id TEXT PRIMARY KEY,
    FileName TEXT NOT NULL,
    FilePath TEXT NOT NULL,
    FileType TEXT,
    FileSize INTEGER,
    Tags TEXT,
    Category TEXT DEFAULT 'Uncategorized',
    IndexedAt TEXT,
    ChunkCount INTEGER DEFAULT 0,
    Summary TEXT
);

Service Enhancements (DocumentService.cs)

• Persistent document indexing (currently appears per-session)
• Background re-indexing when documents change
• Cross-document keyword search
• Auto-generate document summary on import using loaded LLM
• Support for more file types: XLSX, PPTX, HTML, MD

Files to Create/Modify

• [MODIFY] Views/DocumentView.xaml - add library management UI
• [MODIFY] ViewModels/DocumentViewModel.cs - add library management logic
• [MODIFY] Services/DocumentService.cs - persistent indexing, search
• [MODIFY] Services/DatabaseService.cs - add DocumentLibrary table
• [NEW] Models/DocumentLibraryItem.cs

Acceptance Criteria

• Documents organized in categories with custom tags
• Full-text search across all indexed documents
• Quick "Chat with document" action from library
• Documents and indexes persist across app restarts
• Bulk operations (multi-select delete, re-index)
• Auto-summary generated on document import