Implement Mayachain Affiliate Fee Indexer API Endpoint

[premiumjibles]

Description:

Implement a Mayachain coinstack in shapeshift-unchained to provide the affiliate fees API endpoint at https://api.mayachain.shapeshift.com/api/v1/affiliate/fees.

Background:

The revenue-dashboard has been calling a non-existent Mayachain API endpoint since inception. The endpoint was assumed to exist but was never implemented. This has caused all Mayachain affiliate

fees to be silently dropped.

CRITICAL CLARIFICATION:

• This endpoint is NOT external - it's something WE implement in shapeshift-unchained
• Thorchain HAS this: go/coinstacks/thorchain/api/affiliateFees.go (blockchain indexer)
• Mayachain DOES NOT: No go/coinstacks/mayachain/ directory exists
• The "down" status means it was never deployed, not that it's temporarily unavailable
• This is a separate work item from the revenue-dashboard fixes below

Scope:

1. Create go/coinstacks/mayachain/ in shapeshift-unchained repo
2. Copy/adapt from go/coinstacks/thorchain/api/affiliateFees.go
3. Change affiliate identifier from "ss" to "ssmaya" (line 176 in Thorchain)
4. Update affiliate wallet addresses for Mayachain
5. Configure chain-specific RPC endpoints
6. Update native token references (CACAO vs RUNE)
7. Deploy as api.mayachain.shapeshift.com

Acceptance Criteria:

• API endpoint returns affiliate fees in same format as Thorchain
• Memo parsing correctly identifies "ssmaya" swaps
• API filters for Mayachain-specific affiliate addresses
• Integration tests pass
• Endpoint is deployed and accessible

Technical Notes:

• Implementation should be 95% identical to Thorchain
• Reference: /home/sean/Repos/shapeshift-unchained/go/coinstacks/thorchain/api/affiliateFees.go
• The revenue-dashboard code is already written and ready to consume this API