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/backend/cmd/server/main.go

@@ -48,8 +48,8 @@ func main() {
 		log.Println("AUTO_MIGRATE disabled; skipping startup migrations")
 	}
 
-	// Seed demo data in development (or when explicitly requested).
-	if cfg.IsDevelopment() || cfg.SeedDataOnStart {
+	// Seed demo data only when explicitly requested.
+	if cfg.SeedDataOnStart {
 		if err := db.SeedData(); err != nil {
 			log.Printf("Warning: Failed to seed data: %v", err)
 		}