feat(core): sync framework security hardening and accessibility improvements

- add util.Go with panic recovery for background goroutines
- add util.EscapeLike and explicit ESCAPE clause for SQL LIKE queries
- add DummyCheckPassword and subtle.ConstantTimeCompare against timing attacks
- enforce session ID rotation upon login/oauth callback to prevent session fixation
- add sliding window login failure rate limiting and oauth state rate limiting
- fix redis client capture race in pubsub listeners and wait on stop channel
- adjust global --primary to oklch(51.1% 0.262 276.966) for WCAG AA contrast
- fix semantic heading levels and missing aria-labels across UI components
- document security, concurrency, and a11y standards in AGENTS.md

internal/apps/cap/runtime_settings.go

@@ -17,6 +17,7 @@ import (
 	"github.com/Rain-kl/Wavelet/internal/infra/persistence"
 	"github.com/Rain-kl/Wavelet/internal/model"
 	"github.com/Rain-kl/Wavelet/internal/repository"
+	"github.com/Rain-kl/Wavelet/pkg/util"
 )
 
 const (
@@ -190,7 +191,7 @@ func startRuntimeSettingsInvalidationListener() {
 		return
 	}
 
-	go func() {
+	util.Go(func() {
 		pubsub := db.Redis.Subscribe(context.Background(), repository.SystemConfigInvalidationChannel)
 		defer func() {
 			_ = pubsub.Close()
@@ -208,5 +209,5 @@ func startRuntimeSettingsInvalidationListener() {
 				InvalidateRuntimeSettings()
 			}
 		}
-	}()
+	})
 }