Fix inverted transaction type logic causing incorrect status updates

[kevintang513]

Summary

• Fixed critical bug where payment and request transaction logic was inverted
• Payments now correctly complete immediately with status "complete"
• Requests now correctly remain "pending" until accepted/rejected

Changes

File: backend/database.ts

• Line 549: Changed if (isRequestTransaction(transaction)) to if (!isRequestTransaction(transaction))

Root Cause:
The transaction creation logic had inverted conditional logic that caused:

• Payments to be processed as requests (status remained "pending", no balance debit/credit)
• Requests to be processed as payments (status set to "complete", balance immediately debited/credited)

Impact:
This bug broke the fundamental transaction flow:

• Payment transactions were not completing
• Request transactions were auto-completing without user approval
• Balance updates were happening at the wrong time

Test Plan

Unit Tests:

• All unit tests now pass (yarn test:unit:ci)
• Transaction creation tests verify correct status:
  • should create a payment - expects status "complete" ✓
  • should create a request - expects status "pending" ✓

Manual Testing:

1. Start the app (yarn start)
2. Log in as a test user
3. Create a payment transaction:
   • Navigate to "New Transaction"
   • Select a contact and choose "Pay"
   • Submit the transaction
   • Expected: Transaction status should be "complete", balances updated immediately
4. Create a request transaction:
   • Navigate to "New Transaction"
   • Select a contact and choose "Request"
   • Submit the transaction
   • Expected: Transaction status should be "pending", balances unchanged until accepted

Files Changed:

• backend/database.ts (1 line)

Tests Passing:

• 44 unit tests passing
• 0 failures

🤖 Generated with Claude Code

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