Add Paperless Finance Report Tool - Complete implementation

A Python CLI tool for generating financial reports from Paperless-ngx:

- Phase 1 (MVP): Config handling, Paperless API client with auth and
  pagination, custom fields extraction, tag-based summation, CLI output
- Phase 2 (Grouping): Multiple grouping criteria (tag, correspondent,
  category, payment type, month, quarter, year), percentage distribution
- Phase 3 (Reports): HTML reports with Chart.js diagrams (doughnut, bar,
  line charts), PDF export via WeasyPrint, JSON and CSV export
- Phase 4 (Comfort): Automatic tag ID resolution, disk caching with
  diskcache, colorized logging, comprehensive error handling

Features:
- Flexible date filtering (year, month, date range)
- Period comparison with change analysis
- Swiss franc formatting (CHF with apostrophe separators)
- Interactive HTML reports with sortable tables and document links
- Multiple output formats (CLI, HTML, PDF, JSON, CSV)

paperless-report/.gitignore

@@ -0,0 +1,41 @@
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# Virtual environment
+venv/
+env/
+.venv/
+
+# Config with secrets
+config.yaml
+
+# Cache
+.cache/
+
+# Output files
+output/*.html
+output/*.pdf
+output/*.json
+output/*.csv
+
+# IDE
+.idea/
+.vscode/
+*.swp
+*.swo
+
+# Distribution / packaging
+dist/
+build/
+*.egg-info/
+
+# Testing
+.pytest_cache/
+.coverage
+htmlcov/
+
+# Misc
+.DS_Store
+*.log