Fix: Raise an Error for Wrong Input or Output File Formats in Artbox #157

[manikyarathore]

Users could specify incorrect file formats for input/output paths without receiving validation errors. For example, using --output-path /tmp/artbox/speech.md (text format) instead of speech.mp3 (audio format) for text to speech conversion would complete without error, causing downstream operations to fail.

Solution
= Implemented file format validation for Artbox CLI operations:

New Files:
= validators.py - Validator module with validate_io_paths() function

Changes:
= Validates input/output file extensions based on operation type:
text-to-speech (tts): requires audio output (.mp3, .wav, .ogg, .flac, .m4a, .aac)
speech-to-text (stt): requires audio input and text output (.txt, .md, .srt, .vtt, .json)
Infers operation type from file extensions if not explicitly provided
Raises clear, user-friendly error messages with supported format lists
Exits with code 2 on validation failure
Modified Files:

Benefits

1. Catches format errors early, saving user time
2. Clear error messages guide users to correct formats
3. Prevents cascading failures in multi-step operations
4. Works with both explicit and inferred operation types

Test: text to speech with invalid .md output (should fail)

python src/artbox/validators.py --operation text-to-speech --output-path out.md

Test: speech to text with valid formats (should pass)

python src/artbox/validators.py --operation speech-to-text --input-path audio.mp3 --output-path transcript.txt

[xmnlab]

hi @manikyarathore ! this is not the correct place to raise a PR to artbox.
instead take a look at the artbox repo here: https://github.com/osl-incubator/artbox