Add updateContent function and generate shortName for all startups

Summary

This PR implements an AI-powered system to generate concise shortName fields (≤3 words) for all startups and updates the home page to display these instead of truncated names. The implementation includes:

• New AI function (updateContent) that uses GPT-5 to generate shortNames from startup names
• Batch processing script that updated all 558 startup MDX files with generated shortNames
• Home page integration to display shortNames instead of manually truncated names
• Type definitions and component updates to support the new field

All 558 startups now have shortName fields like "FinCast AI", "FlakeFix", "SafePoint AI", etc.

Review & Testing Checklist for Human

• Verify shortName quality - Spot check 10-15 random startup files to ensure generated shortNames are appropriate, concise (≤3 words), and accurately represent the business
• Test home page functionality - Navigate to localhost:3000 and verify startup cards display shortNames correctly instead of truncated names
• Test fallback behavior - Temporarily remove a shortName from a startup file and verify the display falls back to the original name gracefully
• Check startup page routing - Click through to individual startup pages to ensure routing still works correctly (shortName doesn't break slug-based navigation)
• Performance verification - Ensure home page loads within normal timeframes despite processing 558 shortName fields

Recommended test plan: Start dev server, navigate home page, click random startup cards, verify display quality and functionality.

Diagram

%%{ init : { "theme" : "default" }}%%
flowchart TD
    Script["scripts/updateContentShortName.ts"]:::major-edit
    UpdateContent["lib/ai/updateContent.ts"]:::major-edit
    HomePage["app/page.tsx"]:::minor-edit
    StartupCard["components/startup-card.tsx"]:::minor-edit
    Types["types/startup.ts"]:::minor-edit
    Package["package.json"]:::minor-edit
    StartupFiles["startups/*.mdx (558 files)"]:::major-edit
    
    Script --> UpdateContent
    Script --> StartupFiles
    HomePage --> StartupFiles
    HomePage --> StartupCard
    StartupCard --> Types
    
    Script -."generates shortName".-> StartupFiles
    HomePage -."reads shortName".-> StartupFiles
    StartupCard -."displays shortName".-> Types
    
    subgraph Legend
        L1[Major Edit]:::major-edit
        L2[Minor Edit]:::minor-edit
        L3[Context/No Edit]:::context
    end

classDef major-edit fill:#90EE90
classDef minor-edit fill:#87CEEB
classDef context fill:#FFFFFF

Notes

• The script is idempotent - it skips startups that already have shortName fields
• All shortNames were generated using OpenAI GPT-5 with specific prompts for conciseness and business relevance
• Home page now shows more readable names like "FinCast AI" instead of truncated versions like "FinCast AI — Perishable Demand"
• Session info: Requested by Nathan (@nathanclevenger) - Devin session link