feat(add): #8 option to only/exclude files by ext

[danielebriggi]

Ticket #8

[Copilot]

Pull Request Overview

Adds support for selectively including or excluding files by extension when adding documents, and updates tests accordingly.

• Introduces only_extensions and exclude_extensions parameters to CLI, SQLiteRag.add, and FileReader APIs.
• Refactors FileReader.extensions to drop leading dots and enhances filtering logic.
• Expands test coverage for new filtering behavior.

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
tests/test_sqlite_rag.py	Adds tests for add() with only/exclude extension combinations and single-file scenarios.
tests/test_reader.py	Updates existing tests for new extension style and adds comprehensive coverage for only/exclude logic.
src/sqlite_rag/sqliterag.py	Passes new filtering parameters through to FileReader.collect_files.
src/sqlite_rag/reader.py	Refactors extension list format and implements only/exclude filtering in is_supported and collect_files.
src/sqlite_rag/cli.py	Adds CLI options --only / --exclude and parses them into lists.

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}

[codecov]

Codecov Report

❌ Patch coverage is 98.26590% with 3 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
src/sqlite_rag/cli.py	57.14%	3 Missing ⚠️

📢 Thoughts on this report? Let us know!