feat: add SQLite persistence and REST API for temporary whitelisting

- Migrate IP-based temporary whitelisting from file to SQLite storage
- Add REST API endpoints for managing temporary and permanent whitelists
- Create `.env.example` with required environment variables
- Document API endpoints in README.md and docs/api.md
- Add new dependency `modernc.org/sqlite` for SQLite support
- Update deployment and security documentation

auth.go

@@ -6,6 +6,7 @@ import (
 	"log/slog"
 	"net"
 	"net/http"
+	"time"
 )
 
 func CheckAuth(db *sql.DB, r *http.Request) bool {
@@ -130,10 +131,10 @@ func logsHandler(cfg Config, db *sql.DB) http.HandlerFunc {
 				continue
 			}
 			entry := map[string]interface{}{
-				"timestamp": ts,
-				"action":    action,
+				"timestamp":     ts,
+				"action":        action,
 				"api_client_ip": apiClientIP,
-				"reason":    reason,
+				"reason":        reason,
 			}
 			if ip.Valid {
 				entry["ip"] = ip.String
@@ -218,4 +219,4 @@ func verifyAPIKey(r *http.Request, expectedToken string) bool {
 func statusHandler(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "text/plain")
 	w.Write([]byte("ok\n"))
-}
+}