Implement InsertDataset and InsertMetadata in GO (#13883)

### What problem does this PR solve?

Implement InsertDataset and InsertMetadata in GO

new internal cli for go:

INSERT DATASET FROM FILE "file_name"
INSERT METADATA FROM FILE "file_name"

### Type of change

- [x] Refactoring

internal/cli/parser.go

@@ -166,6 +166,8 @@ func (p *Parser) parseUserCommand() (*Command, error) {
 		return p.parseGenerateCommand()
 	case TokenImport:
 		return p.parseImportCommand()
+	case TokenInsert:
+		return p.parseInsertCommand()
 	case TokenSearch:
 		return p.parseSearchCommand()
 	case TokenParse:
@@ -217,7 +219,7 @@ func (p *Parser) expectSemicolon() error {
 }
 
 func isKeyword(tokenType int) bool {
-	return tokenType >= TokenLogin && tokenType <= TokenDocMeta
+	return tokenType >= TokenLogin && tokenType <= TokenMetadata
 }
 
 // isCECommand checks if the given string is a ContextEngine command