feat(channel-monitor): request templates with snapshot apply + headers/body override

Problem:
Upstream channels can reject monitor probes based on client fingerprint
(e.g. "only Claude Code clients allowed"). The monitor had no way to
customize the outgoing request to bypass such restrictions.

Solution:
Introduce reusable request templates that carry extra_headers plus an
optional body override; monitors reference a template and receive a
snapshot copy on apply. Template edits do NOT auto-propagate — users
must click "apply to associated monitors" to refresh snapshots, so a
bad template edit cannot instantly break all production monitors.

Data model (migration 112):
- channel_monitor_request_templates: id, name, provider, description,
  extra_headers jsonb, body_override_mode ('off'|'merge'|'replace'),
  body_override jsonb. Unique (provider, name).
- channel_monitors: +template_id (FK, ON DELETE SET NULL), +extra_headers,
  +body_override_mode, +body_override (the three runtime snapshot fields).

Checker (channel_monitor_checker.go):
- callProvider + runCheckForModel accept a CheckOptions carrying the
  snapshot fields. mergeHeaders applies user headers on top of adapter
  defaults (forbidden list: Host / Content-Length / Transfer-Encoding /
  Connection / Content-Encoding).
- buildRequestBody:
    off     -> adapter default body
    merge   -> shallow-merge over default; per-provider deny list
               (model/messages/contents) protects the challenge contract
    replace -> user body verbatim
- Replace mode skips challenge validation; instead HTTP 2xx + non-empty
  extracted response text = operational, empty = failed.
- 4 new unit tests cover all three modes + replace/empty-response case.

Admin API:
- /admin/channel-monitor-templates CRUD + /:id/apply (overwrite snapshot
  on all template_id=id monitors, returns affected count).
- channel_monitor request/response DTOs gain the 4 new fields.

Frontend:
- channelMonitorTemplate.ts API client.
- MonitorAdvancedRequestConfig.vue shared component for headers textarea
  + body mode radio + body JSON editor; used by both template and monitor
  forms.
- MonitorTemplateManagerDialog.vue: provider tabs, list/create/edit/
  delete/apply, live "associated monitors" count per row.
- MonitorFiltersBar: new 模板管理 button next to 新增监控.
- MonitorFormDialog: collapsible 高级 section with template dropdown
  (filtered by form.provider, clears on provider change) + embedded
  AdvancedRequestConfig. Picking a template copies its fields into the
  form (snapshot semantics mirrored on the client).
- i18n zh/en entries for all new copy.

chore: bump version to 0.1.114.32

backend/ent/channelmonitor/channelmonitor.go

@@ -41,10 +41,20 @@ const (
 	FieldLastCheckedAt = "last_checked_at"
 	// FieldCreatedBy holds the string denoting the created_by field in the database.
 	FieldCreatedBy = "created_by"
+	// FieldTemplateID holds the string denoting the template_id field in the database.
+	FieldTemplateID = "template_id"
+	// FieldExtraHeaders holds the string denoting the extra_headers field in the database.
+	FieldExtraHeaders = "extra_headers"
+	// FieldBodyOverrideMode holds the string denoting the body_override_mode field in the database.
+	FieldBodyOverrideMode = "body_override_mode"
+	// FieldBodyOverride holds the string denoting the body_override field in the database.
+	FieldBodyOverride = "body_override"
 	// EdgeHistory holds the string denoting the history edge name in mutations.
 	EdgeHistory = "history"
 	// EdgeDailyRollups holds the string denoting the daily_rollups edge name in mutations.
 	EdgeDailyRollups = "daily_rollups"
+	// EdgeRequestTemplate holds the string denoting the request_template edge name in mutations.
+	EdgeRequestTemplate = "request_template"
 	// Table holds the table name of the channelmonitor in the database.
 	Table = "channel_monitors"
 	// HistoryTable is the table that holds the history relation/edge.
@@ -61,6 +71,13 @@ const (
 	DailyRollupsInverseTable = "channel_monitor_daily_rollups"
 	// DailyRollupsColumn is the table column denoting the daily_rollups relation/edge.
 	DailyRollupsColumn = "monitor_id"
+	// RequestTemplateTable is the table that holds the request_template relation/edge.
+	RequestTemplateTable = "channel_monitors"
+	// RequestTemplateInverseTable is the table name for the ChannelMonitorRequestTemplate entity.
+	// It exists in this package in order to avoid circular dependency with the "channelmonitorrequesttemplate" package.
+	RequestTemplateInverseTable = "channel_monitor_request_templates"
+	// RequestTemplateColumn is the table column denoting the request_template relation/edge.
+	RequestTemplateColumn = "template_id"
 )
 
 // Columns holds all SQL columns for channelmonitor fields.
@@ -79,6 +96,10 @@ var Columns = []string{
 	FieldIntervalSeconds,
 	FieldLastCheckedAt,
 	FieldCreatedBy,
+	FieldTemplateID,
+	FieldExtraHeaders,
+	FieldBodyOverrideMode,
+	FieldBodyOverride,
 }
 
 // ValidColumn reports if the column name is valid (part of the table columns).
@@ -116,6 +137,12 @@ var (
 	DefaultEnabled bool
 	// IntervalSecondsValidator is a validator for the "interval_seconds" field. It is called by the builders before save.
 	IntervalSecondsValidator func(int) error
+	// DefaultExtraHeaders holds the default value on creation for the "extra_headers" field.
+	DefaultExtraHeaders map[string]string
+	// DefaultBodyOverrideMode holds the default value on creation for the "body_override_mode" field.
+	DefaultBodyOverrideMode string
+	// BodyOverrideModeValidator is a validator for the "body_override_mode" field. It is called by the builders before save.
+	BodyOverrideModeValidator func(string) error
 )
 
 // Provider defines the type for the "provider" enum field.
@@ -210,6 +237,16 @@ func ByCreatedBy(opts ...sql.OrderTermOption) OrderOption {
 	return sql.OrderByField(FieldCreatedBy, opts...).ToFunc()
 }
 
+// ByTemplateID orders the results by the template_id field.
+func ByTemplateID(opts ...sql.OrderTermOption) OrderOption {
+	return sql.OrderByField(FieldTemplateID, opts...).ToFunc()
+}
+
+// ByBodyOverrideMode orders the results by the body_override_mode field.
+func ByBodyOverrideMode(opts ...sql.OrderTermOption) OrderOption {
+	return sql.OrderByField(FieldBodyOverrideMode, opts...).ToFunc()
+}
+
 // ByHistoryCount orders the results by history count.
 func ByHistoryCount(opts ...sql.OrderTermOption) OrderOption {
 	return func(s *sql.Selector) {
@@ -237,6 +274,13 @@ func ByDailyRollups(term sql.OrderTerm, terms ...sql.OrderTerm) OrderOption {
 		sqlgraph.OrderByNeighborTerms(s, newDailyRollupsStep(), append([]sql.OrderTerm{term}, terms...)...)
 	}
 }
+
+// ByRequestTemplateField orders the results by request_template field.
+func ByRequestTemplateField(field string, opts ...sql.OrderTermOption) OrderOption {
+	return func(s *sql.Selector) {
+		sqlgraph.OrderByNeighborTerms(s, newRequestTemplateStep(), sql.OrderByField(field, opts...))
+	}
+}
 func newHistoryStep() *sqlgraph.Step {
 	return sqlgraph.NewStep(
 		sqlgraph.From(Table, FieldID),
@@ -251,3 +295,10 @@ func newDailyRollupsStep() *sqlgraph.Step {
 		sqlgraph.Edge(sqlgraph.O2M, false, DailyRollupsTable, DailyRollupsColumn),
 	)
 }
+func newRequestTemplateStep() *sqlgraph.Step {
+	return sqlgraph.NewStep(
+		sqlgraph.From(Table, FieldID),
+		sqlgraph.To(RequestTemplateInverseTable, FieldID),
+		sqlgraph.Edge(sqlgraph.M2O, false, RequestTemplateTable, RequestTemplateColumn),
+	)
+}

backend/ent/channelmonitor/where.go

@@ -110,6 +110,16 @@ func CreatedBy(v int64) predicate.ChannelMonitor {
 	return predicate.ChannelMonitor(sql.FieldEQ(FieldCreatedBy, v))
 }
 
+// TemplateID applies equality check predicate on the "template_id" field. It's identical to TemplateIDEQ.
+func TemplateID(v int64) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldEQ(FieldTemplateID, v))
+}
+
+// BodyOverrideMode applies equality check predicate on the "body_override_mode" field. It's identical to BodyOverrideModeEQ.
+func BodyOverrideMode(v string) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldEQ(FieldBodyOverrideMode, v))
+}
+
 // CreatedAtEQ applies the EQ predicate on the "created_at" field.
 func CreatedAtEQ(v time.Time) predicate.ChannelMonitor {
 	return predicate.ChannelMonitor(sql.FieldEQ(FieldCreatedAt, v))
@@ -685,6 +695,111 @@ func CreatedByLTE(v int64) predicate.ChannelMonitor {
 	return predicate.ChannelMonitor(sql.FieldLTE(FieldCreatedBy, v))
 }
 
+// TemplateIDEQ applies the EQ predicate on the "template_id" field.
+func TemplateIDEQ(v int64) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldEQ(FieldTemplateID, v))
+}
+
+// TemplateIDNEQ applies the NEQ predicate on the "template_id" field.
+func TemplateIDNEQ(v int64) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldNEQ(FieldTemplateID, v))
+}
+
+// TemplateIDIn applies the In predicate on the "template_id" field.
+func TemplateIDIn(vs ...int64) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldIn(FieldTemplateID, vs...))
+}
+
+// TemplateIDNotIn applies the NotIn predicate on the "template_id" field.
+func TemplateIDNotIn(vs ...int64) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldNotIn(FieldTemplateID, vs...))
+}
+
+// TemplateIDIsNil applies the IsNil predicate on the "template_id" field.
+func TemplateIDIsNil() predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldIsNull(FieldTemplateID))
+}
+
+// TemplateIDNotNil applies the NotNil predicate on the "template_id" field.
+func TemplateIDNotNil() predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldNotNull(FieldTemplateID))
+}
+
+// BodyOverrideModeEQ applies the EQ predicate on the "body_override_mode" field.
+func BodyOverrideModeEQ(v string) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldEQ(FieldBodyOverrideMode, v))
+}
+
+// BodyOverrideModeNEQ applies the NEQ predicate on the "body_override_mode" field.
+func BodyOverrideModeNEQ(v string) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldNEQ(FieldBodyOverrideMode, v))
+}
+
+// BodyOverrideModeIn applies the In predicate on the "body_override_mode" field.
+func BodyOverrideModeIn(vs ...string) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldIn(FieldBodyOverrideMode, vs...))
+}
+
+// BodyOverrideModeNotIn applies the NotIn predicate on the "body_override_mode" field.
+func BodyOverrideModeNotIn(vs ...string) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldNotIn(FieldBodyOverrideMode, vs...))
+}
+
+// BodyOverrideModeGT applies the GT predicate on the "body_override_mode" field.
+func BodyOverrideModeGT(v string) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldGT(FieldBodyOverrideMode, v))
+}
+
+// BodyOverrideModeGTE applies the GTE predicate on the "body_override_mode" field.
+func BodyOverrideModeGTE(v string) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldGTE(FieldBodyOverrideMode, v))
+}
+
+// BodyOverrideModeLT applies the LT predicate on the "body_override_mode" field.
+func BodyOverrideModeLT(v string) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldLT(FieldBodyOverrideMode, v))
+}
+
+// BodyOverrideModeLTE applies the LTE predicate on the "body_override_mode" field.
+func BodyOverrideModeLTE(v string) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldLTE(FieldBodyOverrideMode, v))
+}
+
+// BodyOverrideModeContains applies the Contains predicate on the "body_override_mode" field.
+func BodyOverrideModeContains(v string) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldContains(FieldBodyOverrideMode, v))
+}
+
+// BodyOverrideModeHasPrefix applies the HasPrefix predicate on the "body_override_mode" field.
+func BodyOverrideModeHasPrefix(v string) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldHasPrefix(FieldBodyOverrideMode, v))
+}
+
+// BodyOverrideModeHasSuffix applies the HasSuffix predicate on the "body_override_mode" field.
+func BodyOverrideModeHasSuffix(v string) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldHasSuffix(FieldBodyOverrideMode, v))
+}
+
+// BodyOverrideModeEqualFold applies the EqualFold predicate on the "body_override_mode" field.
+func BodyOverrideModeEqualFold(v string) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldEqualFold(FieldBodyOverrideMode, v))
+}
+
+// BodyOverrideModeContainsFold applies the ContainsFold predicate on the "body_override_mode" field.
+func BodyOverrideModeContainsFold(v string) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldContainsFold(FieldBodyOverrideMode, v))
+}
+
+// BodyOverrideIsNil applies the IsNil predicate on the "body_override" field.
+func BodyOverrideIsNil() predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldIsNull(FieldBodyOverride))
+}
+
+// BodyOverrideNotNil applies the NotNil predicate on the "body_override" field.
+func BodyOverrideNotNil() predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(sql.FieldNotNull(FieldBodyOverride))
+}
+
 // HasHistory applies the HasEdge predicate on the "history" edge.
 func HasHistory() predicate.ChannelMonitor {
 	return predicate.ChannelMonitor(func(s *sql.Selector) {
@@ -731,6 +846,29 @@ func HasDailyRollupsWith(preds ...predicate.ChannelMonitorDailyRollup) predicate
 	})
 }
 
+// HasRequestTemplate applies the HasEdge predicate on the "request_template" edge.
+func HasRequestTemplate() predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(func(s *sql.Selector) {
+		step := sqlgraph.NewStep(
+			sqlgraph.From(Table, FieldID),
+			sqlgraph.Edge(sqlgraph.M2O, false, RequestTemplateTable, RequestTemplateColumn),
+		)
+		sqlgraph.HasNeighbors(s, step)
+	})
+}
+
+// HasRequestTemplateWith applies the HasEdge predicate on the "request_template" edge with a given conditions (other predicates).
+func HasRequestTemplateWith(preds ...predicate.ChannelMonitorRequestTemplate) predicate.ChannelMonitor {
+	return predicate.ChannelMonitor(func(s *sql.Selector) {
+		step := newRequestTemplateStep()
+		sqlgraph.HasNeighborsWith(s, step, func(s *sql.Selector) {
+			for _, p := range preds {
+				p(s)
+			}
+		})
+	})
+}
+
 // And groups predicates with the AND operator between them.
 func And(predicates ...predicate.ChannelMonitor) predicate.ChannelMonitor {
 	return predicate.ChannelMonitor(sql.AndPredicates(predicates...))