[AI-FSSDK] (DO NOT REVIEW) [FSSDK-12262] Exclude CMAB from UserProfileService

[jaeopt]

Summary

CMAB experiments should not use UserProfileService (UPS) for sticky bucketing. UPS maintains decisions across the experiment lifetime without considering TTL or user attributes, which contradicts CMAB's dynamic nature. This change explicitly excludes CMAB experiments from UPS lookup and save operations.

Changes

• Skip UPS stored variation lookup for CMAB experiments in the decision service
• Skip UPS variation save for CMAB experiments after a decision is made
• Add decision reason message explaining CMAB exclusion from UPS
• Add unit tests verifying UPS is skipped for CMAB and still used for non-CMAB experiments

Jira Ticket

FSSDK-12262