[Backlog] Add Delta Sharing and Collaboration cost estimation

[CheeYuTan]

Summary

Add first-class estimation for the Delta Sharing and Collaboration products listed in the Databricks Platform pricing catalog.

Scope

• Research the current billable components for View Sharing, Delta Sharing from SAP Business Data Cloud, and other collaboration offerings in this pricing group.
• Separate provider-side, recipient-side, compute, storage, and data-transfer costs where billing responsibility differs.
• Model practical inputs such as shares/recipients, monthly data volume, refresh/query activity, or capacity units only where official pricing supports them.
• Do not invent rates for free or contract-only capabilities.

Acceptance criteria

• Add supported workload/component types, calculation APIs, and frontend forms.
• Resolve exact regional SKU pricing without cross-region fallback.
• Persist all inputs in workload_config; no database schema migration.
• Show transparent usage → billing units → rate → cost formulas.
• Include AI-assisted estimate creation, cloning, and Excel export.
• Explain additive compute, storage, and transfer costs in the UI.
• Add calculation, validation, persistence, parity, and export tests.
• Validate assumptions against current official pricing before release.

References

• https://www.databricks.com/product/pricing/view-sharing
• https://www.databricks.com/product/pricing/delta-share-sap-business-data-cloud