feat(channel-monitor): apply template via subset picker; CC 2.1.114 baseline doc

Apply flow:
- POST /admin/channel-monitor-templates/:id/apply now requires monitor_ids
  (non-empty array). Service applies the template only to the selected
  subset, gated by AND template_id = :id (so users can't sneak in
  unrelated monitor IDs).
- New GET /admin/channel-monitor-templates/:id/monitors returns the
  associated monitor briefs (id/name/provider/enabled) for the picker.
- ApplyToMonitors signature gains monitorIDs []int64; empty list returns
  ErrChannelMonitorTemplateApplyEmpty.

Frontend:
- New MonitorTemplateApplyPickerDialog.vue: list of associated monitors
  with checkboxes (default all checked), 全选 / 全不选 shortcuts, live
  selected/total count. Submit calls apply(id, ids).
- MonitorTemplateManagerDialog replaces the old ConfirmDialog flow with
  the picker; onApplied refetches the list to refresh associated counts.

i18n: applyPicker* + common.selectAll keys.

chore: bump version to 0.1.114.33

The CC 2.1.114 (sdk-cli) UA / APIKeyBetaHeader / JSON metadata.user_id
baseline (already verified working via the in-process apply on prod
template id=1) is documented in internal/pkg/claude/constants.go and
is what the seed template in the manager UI should follow.

backend/internal/server/routes/admin.go

@@ -587,6 +587,7 @@ func registerChannelMonitorRoutes(admin *gin.RouterGroup, h *handler.Handlers) {
 		templates.GET("/:id", h.Admin.ChannelMonitorTemplate.Get)
 		templates.PUT("/:id", h.Admin.ChannelMonitorTemplate.Update)
 		templates.DELETE("/:id", h.Admin.ChannelMonitorTemplate.Delete)
+		templates.GET("/:id/monitors", h.Admin.ChannelMonitorTemplate.AssociatedMonitors)
 		templates.POST("/:id/apply", h.Admin.ChannelMonitorTemplate.Apply)
 	}
 }