Fix database connection exhaustion in tests by setting max_conns=1
when creating pgxpool via pgxpool.ParseConfig().
- Update setupTestServer() in test_helpers.go
- Update setupSyncTestDB() in sync_integration_test.go
This reduces per-test connection usage from 4 to 1, keeping total
connections well under PostgreSQL's default max_connections=100.
78 tests × 1 connection = 78 connections (down from 312 potential)
Fixes test failures: "FATAL: sorry, too many clients already"
See PROJECT_GUIDELINES.md Testing section for details.
- Remove handler parameter from test function calls
- Update test signatures to match new setupTestServer return values
- Fix compilation errors after test helper refactoring
- Ensure test consistency for opds, queue, and auth endpoints
john-okeefe