Schema Compare extension (#4974)

* extension now working

* fix diff editor title disappearing and remove border from source and target name boxes

* redoing a bunch of stuff that disappeared after rebasing

* add images and add to extensions.ts

* moving a few changes to the right place after rebase

* formatting

* update toolbar svgs

* addressing comments

* add return types

* Adding PR comments

* Adding light and dark theme icons

* Fixing the diff editor title for dark theme

src/sql/workbench/api/common/sqlExtHostTypes.ts

@@ -292,6 +292,7 @@ export enum DataProviderType {
 	AgentServicesProvider = 'AgentServicesProvider',
 	CapabilitiesProvider = 'CapabilitiesProvider',
 	DacFxServicesProvider = 'DacFxServicesProvider',
+	SchemaCompareServicesProvider = 'SchemaCompareServicesProvider',
 	ObjectExplorerNodeProvider = 'ObjectExplorerNodeProvider'
 }
 
@@ -547,3 +548,19 @@ export class ConnectionProfile {
 		return undefined;
 	}
 }
+
+export enum SchemaUpdateAction {
+	Delete = 0,
+	Change = 1,
+	Add = 2
+}
+
+ export enum SchemaDifferenceType {
+	Object = 0,
+	Property = 1
+}
+
+ export enum SchemaCompareEndpointType {
+	database = 0,
+	dacpac = 1
+}