feat: Support OTel and JSON for logs (via log/slog) (#760)

Co-authored-by: Kyle Mendell <kmendell@ofkm.us>

backend/internal/common/env_config.go

@@ -47,6 +47,7 @@ type EnvConfigSchema struct {
 	UiConfigDisabled   bool       `env:"UI_CONFIG_DISABLED"`
 	MetricsEnabled     bool       `env:"METRICS_ENABLED"`
 	TracingEnabled     bool       `env:"TRACING_ENABLED"`
+	LogJSON            bool       `env:"LOG_JSON"`
 	TrustProxy         bool       `env:"TRUST_PROXY"`
 	AnalyticsDisabled  bool       `env:"ANALYTICS_DISABLED"`
 }