Secrets: Implement basic unified secret store service (#45804)

* wip: Implement kvstore for secrets

* wip: Refactor kvstore for secrets

* wip: Add format key function to secrets kvstore sql

* wip: Add migration for secrets kvstore

* Remove unused Key field from secrets kvstore

* Remove secret values from debug logs

* Integrate unified secrets with datasources

* Fix minor issues and tests for kvstore

* Create test service helper for secret store

* Remove encryption tests from datasources

* Move secret operations after datasources

* Fix datasource proxy tests

* Fix legacy data tests

* Add Name to all delete data source commands

* Implement decryption cache on sql secret store

* Fix minor issue with cache and tests

* Use secret type on secret store datasource operations

* Add comments to make create and update clear

* Rename itemFound variable to isFound

* Improve secret deletion and cache management

* Add base64 encoding to sql secret store

* Move secret retrieval to decrypted values function

* Refactor decrypt secure json data functions

* Fix expr tests

* Fix datasource tests

* Fix plugin proxy tests

* Fix query tests

* Fix metrics api tests

* Remove unused fake secrets service from query tests

* Add rename function to secret store

* Add check for error renaming secret

* Remove bus from tests to fix merge conflicts

* Add background secrets migration to datasources

* Get datasource secure json fields from secrets

* Move migration to secret store

* Revert "Move migration to secret store"

This reverts commit 7c3f872072.

* Add secret service to datasource service on tests

* Fix datasource tests

* Remove merge conflict on wire

* Add ctx to data source http transport on prometheus stats collector

* Add ctx to data source http transport on stats collector test

pkg/services/secrets/kvstore/model.go

@@ -0,0 +1,31 @@
+package kvstore
+
+import (
+	"time"
+)
+
+// Item stored in k/v store.
+type Item struct {
+	Id        int64
+	OrgId     *int64
+	Namespace *string
+	Type      *string
+	Value     string
+
+	Created time.Time
+	Updated time.Time
+}
+
+func (i *Item) TableName() string {
+	return "secrets"
+}
+
+type Key struct {
+	OrgId     int64
+	Namespace string
+	Type      string
+}
+
+func (i *Key) TableName() string {
+	return "secrets"
+}