Overhaul: real metrics, Git integration UI, open-source hygiene, root cleanup

Backend:
- GET /services/:id/metrics with real Docker container stats
- DELETE /git/providers/:id and GET repo branches endpoint

Frontend:
- Service detail shows real telemetry or honest empty states
- Live status distinguishes idle/polling/reconnecting
- Git providers section in Settings; repo+branch pickers in Add Service
- Real logo, compact Projects header, canvas fitView fix
- index.css deduplicated (1725 -> 1384 lines)
- Fixed smoke tests, lint errors, ToastProvider/context unification

Repo hygiene:
- Added LICENSE (MIT), CONTRIBUTING.md, SECURITY.md; rewrote README
- Untracked .env.prod and data/letsencrypt secrets; fixed .gitignore
- Removed legacy root src/internal/cmd and stale configs/docs/artifacts
- Moved guides and design references under docs/

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

app/frontend/src/shared/components/EnhancedMetricCard.tsx

@@ -184,7 +184,6 @@ export function CacheMetricCard({
 }: CacheMetricCardProps) {
   const cachePercent = Math.round((cacheMB / totalMB) * 100);
   const nonCachePercent = Math.round((nonCacheMB / totalMB) * 100);
-  const freePercent = 100 - cachePercent - nonCachePercent;
 
   return (
     <div
@@ -316,7 +315,6 @@ export function PerformanceMetricCard({
   percentage,
   upSpeed,
   downSpeed,
-  datasets,
   onClick,
   animationDelay = 0,
 }: PerformanceMetricCardProps) {