sync: bring over remaining release/custom-0.1.115 changes

- Extract PublicSettingsInjectionPayload named struct with drift test
- Add channel_monitor_default_interval_seconds to SSR injection
- Add image_output_price to SupportedModelChip
- Simplify AppSidebar buildSelfNavItems (admins see available channels)
- Add gateway WARN logs for 503 no-available-accounts branches
- Wire ChannelMonitorRunner into provideCleanup for graceful shutdown
- Add migrations 130/131 (CC template userid fix + mimicry field cleanup)
- Clean up fork-only features (sora, claude max simulation, client affinity)
- Remove ~320 obsolete i18n keys
- Add codexUsage utility, WechatServiceButton, BulkEditAccountModal
- Tidy go.sum

backend/internal/service/account_service.go

@@ -30,6 +30,10 @@ type AccountRepository interface {
 	GetByCRSAccountID(ctx context.Context, crsAccountID string) (*Account, error)
 	// FindByExtraField 根据 extra 字段中的键值对查找账号
 	FindByExtraField(ctx context.Context, key string, value any) ([]Account, error)
+	// CountByTLSFingerprintProfile 按 TLS 指纹模板 ID 聚合每个模板当前被多少账号绑定。
+	// 返回 map[profile_id]count；未绑定任何账号的 profile 不出现在 map 中。
+	// 查询走 108_add_tls_fingerprint_profile_id_index.sql 的表达式索引。
+	CountByTLSFingerprintProfile(ctx context.Context) (map[int64]int, error)
 	// ListCRSAccountIDs returns a map of crs_account_id -> local account ID
 	// for all accounts that have been synced from CRS.
 	ListCRSAccountIDs(ctx context.Context) (map[string]int64, error)