consistency: unify SSL enforcement and enum handling across requests

[maximn]

From the AI-native docs audit (B7 in .agents/known-issues.md).

Problem

• SSL: Entities/TimeZone/Request/TimeZoneRequest.cs forces HTTPS via an IsSSL override, while other legacy requests allow IsSSL=false. (All requests reject an API key over plain HTTP, but the policy is inconsistent.)
• Enums: handling is mixed — some response status enums use [EnumMember(Value=...)], others rely on bare member names.

Fix: pick one SSL policy and apply it uniformly; standardize on [EnumMember] (or document the deliberate omissions).

Severity: low.