feat(config, usage): add usage-statistics-enabled option and dynamic toggling

- Introduced `usage-statistics-enabled` configuration to control in-memory usage aggregation.
- Updated API to include handlers for managing `usage-statistics-enabled` and `logging-to-file` options.
- Enhanced `watcher` to log changes to both configurations dynamically.
- Updated documentation and examples to reflect new configuration options.

internal/api/handlers/management/config_basic.go

@@ -12,6 +12,22 @@ func (h *Handler) GetConfig(c *gin.Context) {
 func (h *Handler) GetDebug(c *gin.Context) { c.JSON(200, gin.H{"debug": h.cfg.Debug}) }
 func (h *Handler) PutDebug(c *gin.Context) { h.updateBoolField(c, func(v bool) { h.cfg.Debug = v }) }
 
+// UsageStatisticsEnabled
+func (h *Handler) GetUsageStatisticsEnabled(c *gin.Context) {
+	c.JSON(200, gin.H{"usage-statistics-enabled": h.cfg.UsageStatisticsEnabled})
+}
+func (h *Handler) PutUsageStatisticsEnabled(c *gin.Context) {
+	h.updateBoolField(c, func(v bool) { h.cfg.UsageStatisticsEnabled = v })
+}
+
+// UsageStatisticsEnabled
+func (h *Handler) GetLoggingToFile(c *gin.Context) {
+	c.JSON(200, gin.H{"logging-to-file": h.cfg.LoggingToFile})
+}
+func (h *Handler) PutLoggingToFile(c *gin.Context) {
+	h.updateBoolField(c, func(v bool) { h.cfg.LoggingToFile = v })
+}
+
 // Request log
 func (h *Handler) GetRequestLog(c *gin.Context) { c.JSON(200, gin.H{"request-log": h.cfg.RequestLog}) }
 func (h *Handler) PutRequestLog(c *gin.Context) {

internal/api/server.go

@@ -24,6 +24,7 @@ import (
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/api/middleware"
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/config"
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/logging"
+	"github.com/router-for-me/CLIProxyAPI/v6/internal/usage"
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/util"
 	sdkaccess "github.com/router-for-me/CLIProxyAPI/v6/sdk/access"
 	"github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/auth"
@@ -317,6 +318,14 @@ func (s *Server) setupRoutes() {
 			mgmt.PUT("/debug", s.mgmt.PutDebug)
 			mgmt.PATCH("/debug", s.mgmt.PutDebug)
 
+			mgmt.GET("/logging-to-file", s.mgmt.GetLoggingToFile)
+			mgmt.PUT("/logging-to-file", s.mgmt.PutLoggingToFile)
+			mgmt.PATCH("/logging-to-file", s.mgmt.PutLoggingToFile)
+
+			mgmt.GET("/usage-statistics-enabled", s.mgmt.GetUsageStatisticsEnabled)
+			mgmt.PUT("/usage-statistics-enabled", s.mgmt.PutUsageStatisticsEnabled)
+			mgmt.PATCH("/usage-statistics-enabled", s.mgmt.PutUsageStatisticsEnabled)
+
 			mgmt.GET("/proxy-url", s.mgmt.GetProxyURL)
 			mgmt.PUT("/proxy-url", s.mgmt.PutProxyURL)
 			mgmt.PATCH("/proxy-url", s.mgmt.PutProxyURL)
@@ -575,6 +584,13 @@ func (s *Server) UpdateClients(cfg *config.Config) {
 		}
 	}
 
+	if s.cfg == nil || s.cfg.UsageStatisticsEnabled != cfg.UsageStatisticsEnabled {
+		usage.SetStatisticsEnabled(cfg.UsageStatisticsEnabled)
+		if s.cfg != nil {
+			log.Debugf("usage_statistics_enabled updated from %t to %t", s.cfg.UsageStatisticsEnabled, cfg.UsageStatisticsEnabled)
+		}
+	}
+
 	// Update log level dynamically when debug flag changes
 	if s.cfg.Debug != cfg.Debug {
 		util.SetLogLevel(cfg)

internal/config/config.go

@@ -26,6 +26,9 @@ type Config struct {
 	// LoggingToFile controls whether application logs are written to rotating files or stdout.
 	LoggingToFile bool `yaml:"logging-to-file" json:"logging-to-file"`
 
+	// UsageStatisticsEnabled toggles in-memory usage aggregation; when false, usage data is discarded.
+	UsageStatisticsEnabled bool `yaml:"usage-statistics-enabled" json:"usage-statistics-enabled"`
+
 	// ProxyURL is the URL of an optional proxy server to use for outbound requests.
 	ProxyURL string `yaml:"proxy-url" json:"proxy-url"`
 
@@ -206,6 +209,7 @@ func LoadConfig(configFile string) (*Config, error) {
 	var config Config
 	// Set defaults before unmarshal so that absent keys keep defaults.
 	config.LoggingToFile = true
+	config.UsageStatisticsEnabled = true
 	config.GeminiWeb.Context = true
 	if err = yaml.Unmarshal(data, &config); err != nil {
 		return nil, fmt.Errorf("failed to parse config file: %w", err)

internal/usage/logger_plugin.go

@@ -7,13 +7,17 @@ import (
 	"context"
 	"fmt"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"github.com/gin-gonic/gin"
 	coreusage "github.com/router-for-me/CLIProxyAPI/v6/sdk/cliproxy/usage"
 )
 
+var statisticsEnabled atomic.Bool
+
 func init() {
+	statisticsEnabled.Store(true)
 	coreusage.RegisterPlugin(NewLoggerPlugin())
 }
 
@@ -36,12 +40,21 @@ func NewLoggerPlugin() *LoggerPlugin { return &LoggerPlugin{stats: defaultReques
 //   - ctx: The context for the usage record
 //   - record: The usage record to aggregate
 func (p *LoggerPlugin) HandleUsage(ctx context.Context, record coreusage.Record) {
+	if !statisticsEnabled.Load() {
+		return
+	}
 	if p == nil || p.stats == nil {
 		return
 	}
 	p.stats.Record(ctx, record)
 }
 
+// SetStatisticsEnabled toggles whether in-memory statistics are recorded.
+func SetStatisticsEnabled(enabled bool) { statisticsEnabled.Store(enabled) }
+
+// StatisticsEnabled reports the current recording state.
+func StatisticsEnabled() bool { return statisticsEnabled.Load() }
+
 // RequestStatistics maintains aggregated request metrics in memory.
 type RequestStatistics struct {
 	mu sync.RWMutex
@@ -138,6 +151,9 @@ func (s *RequestStatistics) Record(ctx context.Context, record coreusage.Record)
 	if s == nil {
 		return
 	}
+	if !statisticsEnabled.Load() {
+		return
+	}
 	timestamp := record.RequestedAt
 	if timestamp.IsZero() {
 		timestamp = time.Now()

internal/watcher/watcher.go

@@ -477,6 +477,12 @@ func (w *Watcher) reloadConfig() bool {
 		if oldConfig.RemoteManagement.AllowRemote != newConfig.RemoteManagement.AllowRemote {
 			log.Debugf("  remote-management.allow-remote: %t -> %t", oldConfig.RemoteManagement.AllowRemote, newConfig.RemoteManagement.AllowRemote)
 		}
+		if oldConfig.LoggingToFile != newConfig.LoggingToFile {
+			log.Debugf("  logging-to-file: %t -> %t", oldConfig.LoggingToFile, newConfig.LoggingToFile)
+		}
+		if oldConfig.UsageStatisticsEnabled != newConfig.UsageStatisticsEnabled {
+			log.Debugf("  usage-statistics-enabled: %t -> %t", oldConfig.UsageStatisticsEnabled, newConfig.UsageStatisticsEnabled)
+		}
 	}
 
 	log.Infof("config successfully reloaded, triggering client reload")