Document tier recommendation algorithm and heuristics

[JoshLuedeman]

Description

TierRecommender uses complex heuristics to suggest Azure SQL tiers. These are undocumented, making it impossible for users to understand or challenge recommendations.

Acceptance Criteria

• ADR or technical document explaining recommendation algorithm
• Input factors documented (data size, DTU usage, query patterns, etc.)
• Decision tree or flowchart for tier selection
• Weight/priority of each factor explained
• Edge cases documented (when recommendations may be suboptimal)
• Document how to override recommendations
• Linked from API documentation and user-facing help

Technical Notes

• TierRecommender is in Scaffold.Assessment
• Factors include: AzurePricingService data, performance profile, data profile size
• Should be approachable by both technical and semi-technical users