Replace broad `except Exception` with `except ImportError` for the yake
import and `except (ValueError, TypeError)` for YAKE extraction. Add
logging so failures are no longer silently swallowed.
Fixes#4
_extract_image_from_stdout() failed to find the generated image because
the pipeline prints "Card generated and saved to: generated_card.png"
but the function only tried the full line as a path. Now also tries the
part after the last colon.
Fix two critical bugs that made the Streamlit app completely non-functional:
1. Split subprocess command into properly separated list elements and use
sys.executable instead of hardcoded "python" (#1)
2. Unpack all 3 return values from run_prompt_pipeline() (#2)
Closes#1, closes#2
