Add robust error checks and helpers, improve transaction safety, and refine default templates handling.
- Add api/handlers/test_helpers_test.go with mustUnmarshalResponse and mustScan helpers and update many handler tests to use them or to check json.Unmarshal errors to fail fast.
- Replace direct DB Scan calls in tests with mustScan or explicit error checks to surface query failures.
- Improve transaction rollback handling across codepaths (config handlers, database migrations, transaction utils, CertGenerator) to log rollback errors and avoid silent failures.
- Make WithTransaction/WithTimeoutTransaction/BatchTransaction formatting consistent and add panic-safe rollback logging.
- In main, log a warning instead of ignoring EnsureDefaultDataSources errors.
- Add/cleanup various helper blank assignments and small refactors in services (config_proxy, config_generator) and switch tests to shared response writers (writeJSONResponse/writeResponseBody) where applicable.
- Large cleanup and enhancements in config/defaults.go to preserve string formatting for YAML templates, ensure special fields are quoted/preserved, and tidy whitespace/formatting.
These changes improve test reliability, make DB/tx failures more visible, and ensure default template YAML preserves important string values.
add safety across services: whitelist tables for DeleteInTransaction to prevent dynamic-SQL deletion abuse; remove a deprecated UpdateInTransaction helper. centralize HTTP client creation (HTTPClientWithTimeout/GetHTTPClient) and replace ad-hoc http.Clients with it; limit response body reads with io.LimitReader to avoid unbounded memory use; add better error logging when JSON marshal fails. Improve ConfigProxy cache handling to fetch outside locks, return stale cache on fetch errors, and only lock to swap the cache; add locking to SetCacheDuration and cap error body reads. convert ResourceWatcher isRunning to atomic.Bool for safe concurrent start/stop. Replace sync.Map memoization in id_normalizer with a bounded map protected by RWMutex (maxCacheSize), add cache flush behavior and tests/benchmarks to validate boundedness and hits. Miscellaneous test updates to match new behavior.
