Rebrand to Obsidian with modern UI and auto-refresh

- Renamed project from "Test Artifact Data Lake" to "Obsidian"
- Updated all branding across README, quickstart scripts, and API
- Implemented dark mode theme with professional color palette
- Simplified table to 4 essential columns (Sim Source, Artifacts, Date, Uploaded By)
- Replaced emoji icons with Lucide SVG icons for better scaling
- Added auto-refresh functionality (5-second intervals, toggleable)
- Enhanced UI with modern flexbox layouts and hover effects
- Updated upload form labels to match new terminology

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

quickstart.ps1

@@ -1,7 +1,7 @@
 # Test Artifact Data Lake - Quick Start (PowerShell)
 
 Write-Host "=========================================" -ForegroundColor Cyan
-Write-Host "Test Artifact Data Lake - Quick Start" -ForegroundColor Cyan
+Write-Host "Obsidian - Quick Start" -ForegroundColor Cyan
 Write-Host "=========================================" -ForegroundColor Cyan
 Write-Host ""