This update tidies the Sales Loyalty module by reorganizing files, improving naming, and standardizing formatting. It does not change business functionality, but makes the module easier to maintain and reduces the risk of future errors.

---
I confirm I have signed the CLA and read the PR guidelines at www.odoo.com/submit-pr

This update reorganizes several internal Discuss components into the Discuss area of the Mail module. It does not introduce new business features, but it helps keep the codebase cleaner and easier to maintain for future improvements.

Part of task-3265211