Add week1 day1 priority digest notebook (Guillermo)

[guillermorosasnegron]

This PR adds a new notebook under community-contributions/guillermo/:

• week1_day1_priority_digest_llm.ipynb

The notebook re-implements the Week 1 Day 1 class with a “priority digest” LLM workflow based on the Eisenhower Matrix (urgent/important quadrants), including:

• dotenv + OpenAI client setup
• a structured prompt organized into Eisenhower priority quadrants
• comments and explanations in Spanish for learning

Goal: practice the full LLM pipeline (from prompt design to model call) and provide a clear, commented example that helps other students apply LLMs to task prioritization using the Eisenhower method.

[ed-donner]

Sounds interesting - but you seem to have only included 1 empty file in this PR?