Refactor log level mapping for HTTP 4XX responses

[ClaraTersi]

Currently, HTTP 4XX responses are logged as error, which causes unnecessary alerts and noise in monitoring dashboards. This behavior suggests a misconfigured log level mapping. We need to refactor the log mapping to align with best practices and ensure consistent signal quality.

Acceptance Criteria

• HTTP 2XX → no log, or info/debug only if explicitly required
• HTTP 3XX → info (optional, depending on relevance)
• HTTP 4XX → info by default; warn only for cases that may indicate misuse (e.g., 401, 403, 429)
• HTTP 5XX → error (always)
• Log level usage is consistent across all Midaz services
• Dashboards and alerts reflect meaningful signals (no false positives from client errors)

[linear]

MDZ-146