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/user_parser.go

@@ -32,6 +32,21 @@ func (p *Parser) parseLoginUser() (*Command, error) {
 	cmd.Params["email"] = email
 
 	p.nextToken()
+	// Optional: WITH PASSWORD 'password'
+	if p.curToken.Type == TokenWith {
+		p.nextToken()
+		if p.curToken.Type != TokenPassword {
+			return nil, fmt.Errorf("expected PASSWORD after WITH")
+		}
+		p.nextToken()
+		password, err := p.parseQuotedString()
+		if err != nil {
+			return nil, err
+		}
+		cmd.Params["password"] = password
+		p.nextToken()
+	}
+
 	// Semicolon is optional for UNSET TOKEN
 	if p.curToken.Type == TokenSemicolon {
 		p.nextToken()
@@ -1531,6 +1546,88 @@ func (p *Parser) parseImportCommand() (*Command, error) {
 	return cmd, nil
 }
 
+// parseInsertCommand parses INSERT command and dispatches to specific handler
+func (p *Parser) parseInsertCommand() (*Command, error) {
+	p.nextToken() // consume INSERT
+
+	// Expect DATASET or METADATA
+	if p.curToken.Type == TokenDataset {
+		return p.parseInsertDatasetFromFile()
+	}
+	if p.curToken.Type == TokenMetadata {
+		return p.parseInsertMetadataFromFile()
+	}
+	return nil, fmt.Errorf("expected DATASET or METADATA after INSERT, got %s", p.curToken.Value)
+}
+
+// Internal CLI for GO
+// parseInsertDatasetFromFile parses: INSERT DATASET FROM FILE "file_path"
+func (p *Parser) parseInsertDatasetFromFile() (*Command, error) {
+	p.nextToken() // consume DATASET
+
+	// Expect FROM
+	if p.curToken.Type != TokenFrom {
+		return nil, fmt.Errorf("expected FROM, got %s", p.curToken.Value)
+	}
+	p.nextToken()
+
+	// Expect FILE
+	if p.curToken.Type != TokenFile {
+		return nil, fmt.Errorf("expected FILE, got %s", p.curToken.Value)
+	}
+	p.nextToken()
+
+	// Get file path (quoted string)
+	filePath, err := p.parseQuotedString()
+	if err != nil {
+		return nil, err
+	}
+
+	cmd := NewCommand("insert_dataset_from_file")
+	cmd.Params["file_path"] = filePath
+
+	p.nextToken()
+	// Semicolon is optional
+	if p.curToken.Type == TokenSemicolon {
+		p.nextToken()
+	}
+	return cmd, nil
+}
+
+// Internal CLI for GO
+// parseInsertMetadataFromFile parses: INSERT INTO METADATA FROM FILE "file_path"
+func (p *Parser) parseInsertMetadataFromFile() (*Command, error) {
+	p.nextToken() // consume METADATA
+
+	// Expect FROM
+	if p.curToken.Type != TokenFrom {
+		return nil, fmt.Errorf("expected FROM, got %s", p.curToken.Value)
+	}
+	p.nextToken()
+
+	// Expect FILE
+	if p.curToken.Type != TokenFile {
+		return nil, fmt.Errorf("expected FILE, got %s", p.curToken.Value)
+	}
+	p.nextToken()
+
+	// Get file path (quoted string)
+	filePath, err := p.parseQuotedString()
+	if err != nil {
+		return nil, err
+	}
+
+	cmd := NewCommand("insert_metadata_from_file")
+	cmd.Params["file_path"] = filePath
+
+	p.nextToken()
+	// Semicolon is optional
+	if p.curToken.Type == TokenSemicolon {
+		p.nextToken()
+	}
+	return cmd, nil
+}
+
 func (p *Parser) parseSearchCommand() (*Command, error) {
 	p.nextToken() // consume SEARCH
 	question, err := p.parseQuotedString()
@@ -1687,6 +1784,8 @@ func (p *Parser) parseUserStatement() (*Command, error) {
 		return p.parseParseCommand()
 	case TokenImport:
 		return p.parseImportCommand()
+	case TokenInsert:
+		return p.parseInsertCommand()
 	case TokenSearch:
 		return p.parseSearchCommand()
 	default: