Add `product-support` skill

[niravpatel27]

Summary

Add a product-support skill that helps investigate and resolve user-reported issues — searching logs, tracing errors, and suggesting fixes or workarounds.

What this skill should do

• Help reproduce a reported issue from a description
• Guide searching logs and error traces
• Suggest likely root causes based on symptoms
• Recommend short-term workarounds and long-term fixes
• Help draft a clear response to the user

Reference

See existing skills like lfx-research/SKILL.md for pattern and format.
Each skill lives in its own directory with a SKILL.md file and markdown instructions.

Acceptance Criteria

• product-support/SKILL.md exists with correct frontmatter
• Skill guides through investigation of a sample support ticket