fix(featureflags): use proto entity and proto json serializer (#7708)

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- Good: "Modified FailoverDomain mapper to allow null ActiveClusterName
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**What changed?**
#7707

Use proto entity of `FeatureFlags` instead so it's consistent across
languages. It's backward/forward compatible because the proto json
marshaler returns the same result with thrift IDL by
cadence-workflow/cadence-idl#245


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**Why?**

Proto has better language consistency than thrift. 

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**How did you test it?**

Added Unit Test to make sure the thrift marshaled json string can be
deserialized into Proto entity.

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**Potential risks**


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## Reviewer Validation

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---------

Signed-off-by: Shijie Sheng <liouvetren@gmail.com>

Author: shijiesheng

.gen/go/shared/shared.go

@@ -40,7 +40,7 @@ require (
 	github.com/startreedata/pinot-client-go v0.2.0 // latest release supports pinot v0.12.0 which is also internal version
 	github.com/stretchr/testify v1.10.0
 	github.com/uber-go/tally v3.3.15+incompatible
-	github.com/uber/cadence-idl v0.0.0-20260115163036-f68403083e26
+	github.com/uber/cadence-idl v0.0.0-20260213213208-6fb822717d01
 	github.com/uber/ringpop-go v0.8.5 // indirect
 	github.com/uber/tchannel-go v1.22.2 // indirect
 	github.com/valyala/fastjson v1.4.1 // indirect

.gen/proto/history/v1/service.pb.yarpc.go

@@ -414,8 +414,8 @@ github.com/uber-go/tally v3.3.12+incompatible/go.mod h1:YDTIBxdXyOU/sCWilKB4bgyu
 github.com/uber-go/tally v3.3.15+incompatible h1:9hLSgNBP28CjIaDmAuRTq9qV+UZY+9PcvAkXO4nNMwg=
 github.com/uber-go/tally v3.3.15+incompatible/go.mod h1:YDTIBxdXyOU/sCWilKB4bgyufu1cEi0jdVnRdxvjnmU=
 github.com/uber/cadence-idl v0.0.0-20211111101836-d6b70b60eb8c/go.mod h1:oyUK7GCNCRHCCyWyzifSzXpVrRYVBbAMHAzF5dXiKws=
-github.com/uber/cadence-idl v0.0.0-20260115163036-f68403083e26 h1:ayljsfgiQNLzoA1Bn29LyRPhFdU9gPKq/1zCUjC8cHE=
-github.com/uber/cadence-idl v0.0.0-20260115163036-f68403083e26/go.mod h1:oyUK7GCNCRHCCyWyzifSzXpVrRYVBbAMHAzF5dXiKws=
+github.com/uber/cadence-idl v0.0.0-20260213213208-6fb822717d01 h1:qHVlPoKvvtivJoSqQiQr6fBGK+SBjiApbM8V+Iw+VRU=
+github.com/uber/cadence-idl v0.0.0-20260213213208-6fb822717d01/go.mod h1:oyUK7GCNCRHCCyWyzifSzXpVrRYVBbAMHAzF5dXiKws=
 github.com/uber/jaeger-client-go v2.22.1+incompatible h1:NHcubEkVbahf9t3p75TOCR83gdUHXjRJvjoBh1yACsM=
 github.com/uber/jaeger-client-go v2.22.1+incompatible/go.mod h1:WVhlPFC8FDjOFMMWRy2pZqQJSXxYSwNYOkTr/Z6d3Kk=
 github.com/uber/jaeger-lib v2.2.0+incompatible h1:MxZXOiR2JuoANZ3J6DE/U0kSFv/eJ/GfSYVCjK7dyaw=

.gen/proto/matching/v1/service.pb.yarpc.go

@@ -24,11 +24,11 @@ package client
 
 import (
 	"context"
-	"encoding/json"
 	"fmt"
 
+	"github.com/gogo/protobuf/jsonpb"
 	"github.com/hashicorp/go-version"
-	"go.uber.org/cadence/client"
+	apiv1 "github.com/uber/cadence-idl/go/proto/api/v1"
 	"go.uber.org/yarpc"
 
 	"github.com/uber/cadence/.gen/go/shared"
@@ -86,8 +86,8 @@ var (
 	ErrUnknownFeature = &types.BadRequestError{Message: "Unknown feature"}
 
 	// DefaultCLIFeatureFlags is the default FeatureFlags used by Cadence CLI
-	DefaultCLIFeatureFlags = shared.FeatureFlags{
-		WorkflowExecutionAlreadyCompletedErrorEnabled: common.BoolPtr(true),
+	DefaultCLIFeatureFlags = apiv1.FeatureFlags{
+		WorkflowExecutionAlreadyCompletedErrorEnabled: true,
 	}
 )
 
@@ -99,7 +99,7 @@ type (
 		SupportsStickyQuery(clientImpl string, clientFeatureVersion string) error
 		SupportsConsistentQuery(clientImpl string, clientFeatureVersion string) error
 		SupportsRawHistoryQuery(clientImpl string, clientFeatureVersion string) error
-		SupportsWorkflowAlreadyCompletedError(clientImpl string, clientFeatureVersion string, featureFlags shared.FeatureFlags) error
+		SupportsWorkflowAlreadyCompletedError(clientImpl string, clientFeatureVersion string, featureFlags apiv1.FeatureFlags) error
 	}
 
 	versionChecker struct {
@@ -109,39 +109,29 @@ type (
 	}
 )
 
-// ToClientFeatureFlags returns Cadence client FeatureFlags version of idl.FeatureFlags
-func ToClientFeatureFlags(featureFlags *shared.FeatureFlags) client.FeatureFlags {
-	flags := client.FeatureFlags{}
-	if featureFlags != nil {
-		if featureFlags.WorkflowExecutionAlreadyCompletedErrorEnabled != nil {
-			flags.WorkflowExecutionAlreadyCompletedErrorEnabled = *featureFlags.WorkflowExecutionAlreadyCompletedErrorEnabled
-		}
-	}
-	return flags
-}
-
 // FeatureFlagsHeader returns the serialized version of the FeatureFlags
-func FeatureFlagsHeader(featureFlags shared.FeatureFlags) string {
-	serialized := ""
-	buf, err := json.Marshal(featureFlags)
-	if err == nil {
-		serialized = string(buf)
+func FeatureFlagsHeader(featureFlags apiv1.FeatureFlags) string {
+	var marshaler jsonpb.Marshaler
+	serialized, err := marshaler.MarshalToString(&featureFlags)
+	if err != nil {
+		// fail open and return empty feature flags
+		return ""
 	}
 	return serialized
 }
 
 // GetFeatureFlagsFromHeader returns FeatureFlags from yarpc headers
-func GetFeatureFlagsFromHeader(call *yarpc.Call) shared.FeatureFlags {
+func GetFeatureFlagsFromHeader(call *yarpc.Call) apiv1.FeatureFlags {
 	featureFlagsSerialized := call.Header(common.ClientFeatureFlagsHeaderName)
 
-	if len(featureFlagsSerialized) > 0 {
-		featureFlags := shared.FeatureFlags{}
-		errSerialize := json.Unmarshal([]byte(featureFlagsSerialized), &featureFlags)
-		if errSerialize == nil {
-			return featureFlags
-		}
+	var featureFlags apiv1.FeatureFlags
+	err := jsonpb.UnmarshalString(featureFlagsSerialized, &featureFlags)
+	if err != nil {
+		// fail open and return empty feature flags
+		return apiv1.FeatureFlags{}
 	}
-	return shared.FeatureFlags{}
+
+	return featureFlags
 }
 
 // NewVersionChecker constructs a new VersionChecker
@@ -224,8 +214,8 @@ func (vc *versionChecker) SupportsRawHistoryQuery(clientImpl string, clientFeatu
 // Returns error if workflowAlreadyCompletedError is not supported otherwise nil.
 // In case client version lookup fails assume the client does not support feature.
 // NOTE: Enabling this error will break customer code handling the workflow errors in their workflow
-func (vc *versionChecker) SupportsWorkflowAlreadyCompletedError(clientImpl string, clientFeatureVersion string, featureFlags shared.FeatureFlags) error {
-	if featureFlags.WorkflowExecutionAlreadyCompletedErrorEnabled != nil && *featureFlags.WorkflowExecutionAlreadyCompletedErrorEnabled {
+func (vc *versionChecker) SupportsWorkflowAlreadyCompletedError(clientImpl string, clientFeatureVersion string, featureFlags apiv1.FeatureFlags) error {
+	if featureFlags.WorkflowExecutionAlreadyCompletedErrorEnabled {
 		return vc.featureSupported(clientImpl, clientFeatureVersion, workflowAlreadyCompletedError)
 	}
 	return &shared.FeatureNotEnabledError{FeatureFlag: "WorkflowExecutionAlreadyCompletedErrorEnabled"}