refactor: upgrade to Go 1.26 and modernize code idioms

- Replace `interface{}` with `any` type alias across all packages
- Use built-in `min()`/`max()` for parameter clamping
- Use `slices.SortFunc`, `slices.Min`, `slices.Max` for cleaner code
- Use `strings.Cut()` for simpler string parsing in auth middleware
- Use `errors.Is()` for proper error comparison in handlers
- Update dependencies: golang.org/x/image 0.37.0 -> 0.38.0
- Add Wire code generation guidelines to ARCHITECTURE.md
- Disable Go cache in CI build workflow

internal/pkg/hook/metrics.go

@@ -103,7 +103,7 @@ func (m *Metrics) GetHookMetrics() []MetricSnapshot {
 }
 
 func parseKey(key string) (HookType, string) {
-	for i := 0; i < len(key); i++ {
+	for i := range len(key) {
 		if key[i] == ':' {
 			return HookType(key[:i]), key[i+1:]
 		}