Integrate BACKBEAT SDK and resolve KACHING license validation

Major integrations and fixes:
- Added BACKBEAT SDK integration for P2P operation timing
- Implemented beat-aware status tracking for distributed operations
- Added Docker secrets support for secure license management
- Resolved KACHING license validation via HTTPS/TLS
- Updated docker-compose configuration for clean stack deployment
- Disabled rollback policies to prevent deployment failures
- Added license credential storage (CHORUS-DEV-MULTI-001)

Technical improvements:
- BACKBEAT P2P operation tracking with phase management
- Enhanced configuration system with file-based secrets
- Improved error handling for license validation
- Clean separation of KACHING and CHORUS deployment stacks

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

vendor/github.com/blevesearch/bleve/v2/search/explanation.go

@@ -0,0 +1,56 @@
+//  Copyright (c) 2014 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package search
+
+import (
+	"encoding/json"
+	"fmt"
+	"reflect"
+
+	"github.com/blevesearch/bleve/v2/size"
+)
+
+var reflectStaticSizeExplanation int
+
+func init() {
+	var e Explanation
+	reflectStaticSizeExplanation = int(reflect.TypeOf(e).Size())
+}
+
+type Explanation struct {
+	Value        float64        `json:"value"`
+	Message      string         `json:"message"`
+	PartialMatch bool           `json:"partial_match,omitempty"`
+	Children     []*Explanation `json:"children,omitempty"`
+}
+
+func (expl *Explanation) String() string {
+	js, err := json.MarshalIndent(expl, "", "  ")
+	if err != nil {
+		return fmt.Sprintf("error serializing explanation to json: %v", err)
+	}
+	return string(js)
+}
+
+func (expl *Explanation) Size() int {
+	sizeInBytes := reflectStaticSizeExplanation + size.SizeOfPtr +
+		len(expl.Message)
+
+	for _, entry := range expl.Children {
+		sizeInBytes += entry.Size()
+	}
+
+	return sizeInBytes
+}