Add TLS standardization for platform, mongo, gateway & redis roles

[Amunagala-itential]

PKI Standardization and Hostname-Based Certificate Support

Summary

Standardized PKI implementation across MongoDB, Redis, Platform, and Gateway roles with hostname-based certificate naming to support multi-server deployments with unique certificates per host.

Problem

• Hardcoded certificate names (server.pem, redis.crt) prevented multi-server deployments
• Inconsistent PKI paths across roles (/etc/ssl/, /opt/itential/)
• No flexible certificate strategy support (per-host, per-role, wildcard)

Solution

• Hostname-based certificate naming using {{ inventory_hostname }}
• Standardized PKI directory structure (/etc/pki/*)
• Comprehensive PKI variables for all roles
• Certificate preparation automation script
• Support for 3 deployment scenarios via configuration

[steven-schattenberg-itential]

There are also some changes I anticipate to set the appropriate SE Linux labels on files. We can address that separately.