Duplicate skill entries in catalog

[crtahlin]

Problem

The skills catalog contains duplicate entries:

Title	Price	Seller
Ethical Guidelines	1 ETH	0xb9d67b9b8431682c6272c38f3b295197fc455dac
Ethical Guidelines	1 ETH	0x02c3462495142e3a931782990eb39946e039b2ba

Same title, same price, different sellers. This could be:

• Intentional (different sellers offering same skill)
• Data quality issue (duplicate submissions)
• Lack of uniqueness validation

Impact

• Minor user confusion
• Unclear which to choose
• May indicate broader data quality issues

Questions

1. Is this intentional? Can multiple sellers offer identically-named skills?
2. Should there be title uniqueness per seller?
3. Should duplicates be merged or differentiated?

Suggested Solutions

If intentional (multiple sellers OK):

• Show seller name/reputation more prominently on cards
• Add "by {seller}" to distinguish

If unintentional:

• Add unique constraint on (title, seller)
• De-duplicate existing data

Acceptance Criteria

• Decision made on whether duplicates are allowed
• If allowed: clear differentiation in UI
• If not allowed: validation prevents duplicates