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/handler/admin/channel_monitor_template_handler.go

@@ -179,17 +179,56 @@ func (h *ChannelMonitorRequestTemplateHandler) Delete(c *gin.Context) {
 	response.Success(c, nil)
 }
 
+type channelMonitorTemplateApplyRequest struct {
+	// MonitorIDs 必填、非空：用户在 picker 里勾选的要被覆盖的监控 ID 列表。
+	// 仅当对应监控当前 template_id == :id 时才会真的被覆盖。
+	MonitorIDs []int64 `json:"monitor_ids" binding:"required,min=1"`
+}
+
 // Apply POST /api/v1/admin/channel-monitor-templates/:id/apply
-// 一键把模板当前配置覆盖到所有关联监控上。
+// 把模板当前配置覆盖到 monitor_ids 列表里的关联监控（picker 选中的子集）。
 func (h *ChannelMonitorRequestTemplateHandler) Apply(c *gin.Context) {
 	id, ok := parseTemplateID(c)
 	if !ok {
 		return
 	}
-	affected, err := h.templateService.ApplyToMonitors(c.Request.Context(), id)
+	var req channelMonitorTemplateApplyRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		response.ErrorFrom(c, infraerrors.BadRequest("VALIDATION_ERROR", err.Error()))
+		return
+	}
+	affected, err := h.templateService.ApplyToMonitors(c.Request.Context(), id, req.MonitorIDs)
 	if err != nil {
 		response.ErrorFrom(c, err)
 		return
 	}
 	response.Success(c, gin.H{"affected": affected})
 }
+
+type associatedMonitorBriefResponse struct {
+	ID       int64  `json:"id"`
+	Name     string `json:"name"`
+	Provider string `json:"provider"`
+	Enabled  bool   `json:"enabled"`
+}
+
+// AssociatedMonitors GET /api/v1/admin/channel-monitor-templates/:id/monitors
+// 列出关联监控（picker 弹窗用）。
+func (h *ChannelMonitorRequestTemplateHandler) AssociatedMonitors(c *gin.Context) {
+	id, ok := parseTemplateID(c)
+	if !ok {
+		return
+	}
+	items, err := h.templateService.ListAssociatedMonitors(c.Request.Context(), id)
+	if err != nil {
+		response.ErrorFrom(c, err)
+		return
+	}
+	out := make([]associatedMonitorBriefResponse, 0, len(items))
+	for _, m := range items {
+		out = append(out, associatedMonitorBriefResponse{
+			ID: m.ID, Name: m.Name, Provider: m.Provider, Enabled: m.Enabled,
+		})
+	}
+	response.Success(c, gin.H{"items": out})
+}