🚚 Refactor(ratio_setting): refactor ratio management into standalone ratio_setting package

Summary
• Migrated all ratio-related sources into `setting/ratio_setting/`
  – `model_ratio.go` (renamed from model-ratio.go)
  – `cache_ratio.go`
  – `group_ratio.go`
• Changed package name to `ratio_setting` and relocated initialization (`ratio_setting.InitRatioSettings()` in main).
• Updated every import & call site:
  – Model / cache / completion / image ratio helpers
  – Group ratio helpers (`GetGroupRatio*`, `ContainsGroupRatio`, `CheckGroupRatio`, etc.)
  – JSON-serialization & update helpers (`*Ratio2JSONString`, `Update*RatioByJSONString`)
• Adjusted controllers, middleware, relay helpers, services and models to reference the new package.
• Removed obsolete `setting` / `operation_setting` imports; added missing `ratio_setting` imports.
• Adopted idiomatic map iteration (`for key := range m`) where value is unused.
• Ran static checks to ensure clean build.

This commit centralises all ratio configuration (model, cache and group) in one cohesive module, simplifying future maintenance and improving code clarity.

setting/ratio_setting/group_ratio.go

@@ -0,0 +1,122 @@
+package ratio_setting
+
+import (
+	"encoding/json"
+	"errors"
+	"one-api/common"
+	"sync"
+)
+
+var groupRatio = map[string]float64{
+	"default": 1,
+	"vip":     1,
+	"svip":    1,
+}
+var groupRatioMutex sync.RWMutex
+
+var (
+	GroupGroupRatio = map[string]map[string]float64{
+		"vip": {
+			"edit_this": 0.9,
+		},
+	}
+	groupGroupRatioMutex sync.RWMutex
+)
+
+func GetGroupRatioCopy() map[string]float64 {
+	groupRatioMutex.RLock()
+	defer groupRatioMutex.RUnlock()
+
+	groupRatioCopy := make(map[string]float64)
+	for k, v := range groupRatio {
+		groupRatioCopy[k] = v
+	}
+	return groupRatioCopy
+}
+
+func ContainsGroupRatio(name string) bool {
+	groupRatioMutex.RLock()
+	defer groupRatioMutex.RUnlock()
+
+	_, ok := groupRatio[name]
+	return ok
+}
+
+func GroupRatio2JSONString() string {
+	groupRatioMutex.RLock()
+	defer groupRatioMutex.RUnlock()
+
+	jsonBytes, err := json.Marshal(groupRatio)
+	if err != nil {
+		common.SysError("error marshalling model ratio: " + err.Error())
+	}
+	return string(jsonBytes)
+}
+
+func UpdateGroupRatioByJSONString(jsonStr string) error {
+	groupRatioMutex.Lock()
+	defer groupRatioMutex.Unlock()
+
+	groupRatio = make(map[string]float64)
+	return json.Unmarshal([]byte(jsonStr), &groupRatio)
+}
+
+func GetGroupRatio(name string) float64 {
+	groupRatioMutex.RLock()
+	defer groupRatioMutex.RUnlock()
+
+	ratio, ok := groupRatio[name]
+	if !ok {
+		common.SysError("group ratio not found: " + name)
+		return 1
+	}
+	return ratio
+}
+
+func GetGroupGroupRatio(group, name string) (float64, bool) {
+	groupGroupRatioMutex.RLock()
+	defer groupGroupRatioMutex.RUnlock()
+
+	gp, ok := GroupGroupRatio[group]
+	if !ok {
+		return -1, false
+	}
+	ratio, ok := gp[name]
+	if !ok {
+		return -1, false
+	}
+	return ratio, true
+}
+
+func GroupGroupRatio2JSONString() string {
+	groupGroupRatioMutex.RLock()
+	defer groupGroupRatioMutex.RUnlock()
+
+	jsonBytes, err := json.Marshal(GroupGroupRatio)
+	if err != nil {
+		common.SysError("error marshalling group-group ratio: " + err.Error())
+	}
+	return string(jsonBytes)
+}
+
+func UpdateGroupGroupRatioByJSONString(jsonStr string) error {
+	groupGroupRatioMutex.Lock()
+	defer groupGroupRatioMutex.Unlock()
+
+	GroupGroupRatio = make(map[string]map[string]float64)
+	return json.Unmarshal([]byte(jsonStr), &GroupGroupRatio)
+}
+
+func CheckGroupRatio(jsonStr string) error {
+	checkGroupRatio := make(map[string]float64)
+	err := json.Unmarshal([]byte(jsonStr), &checkGroupRatio)
+	if err != nil {
+		return err
+	}
+	for name, ratio := range checkGroupRatio {
+		if ratio < 0 {
+			return errors.New("group ratio must be not less than 0: " + name)
+		}
+	}
+	return nil
+}