Update data modeling guide with balanced trade-offs discussion

[mintlify]

Summary

• Restructured the wide tables section to present trade-offs across performance, self-serve usability, and analytical depth
• Added comparison table and guidance on when each approach works best
• Documented common customer patterns (wide tables only, both pathways, multi-join only)
• Added new section on pre-aggregates as a performance optimization
• Removed the strong push for wide tables in favor of balanced guidance

[github-actions]

🤖 Documentation Bot

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[github-actions]

🤖 Documentation Bot

✅ All checks passed! No issues found.