Add Row Text Splitter node for line-based document chunking

[Dexterity104]

Summary

Add a new Row Text Splitter node under Text Splitters in packages/components.
It's meant for line-based content (CSV-style data, table exports, logs) where each row should become its own document.

Closes #6112

What's included

• New RowTextSplitter node wired into the existing TextSplitter ecosystem
• Config options:
  • Line Separator (defaults to \n, supports escaped values like \r\n, \t)
  • Trim Whitespace toggle
  • Include Empty Lines toggle
• Implementation extends LangChain’s TextSplitter, so it works with:
  • splitText
  • splitDocuments
  • createDocuments
• Keeps incoming metadata and adds line-based loc info

Behavior

For input:

id,name,age
1,Alice,30
2,Bob,25
3,Charlie,40

With defaults (separator \n, trim on, empty lines off), the splitter produces four chunks:

1. id,name,age
2. 1,Alice,30
3. 2,Bob,25
4. 3,Charlie,40

Each line is a separate document, aligned exactly with the original rows.

[gemini-code-assist]

Code Review

This pull request introduces the RowTextSplitter component, which enables splitting text into individual rows based on a configurable separator. The implementation includes options for trimming whitespace and filtering empty lines, as well as a node wrapper for integration. A review comment suggests optimizing the line-splitting logic by using a regular expression to handle both LF and CRLF line endings more efficiently during the split operation, rather than performing replacements within a loop.

[gemini-code-assist]

The current implementation of line splitting and carriage return handling can be optimized. Performing a regex replacement inside a loop for every line is less efficient than handling it during the split operation, especially for large documents like logs or CSVs. Using a regex in the split method when the separator is a newline is a more performant and idiomatic approach to handle both LF and CRLF line endings.

Suggested change

	const rawLines = text.split(this.lineSeparator)
	const lines: string[] = []
	for (let raw of rawLines) {
	if (this.lineSeparator === '\n') {
	raw = raw.replace(/\r$/, '')
	}
	const rawLines = this.lineSeparator === '\n' ? text.split(/\r?\n/) : text.split(this.lineSeparator)
	const lines: string[] = []
	for (const raw of rawLines) {

References

1. Prioritize code readability and understandability over conciseness. A series of simple, chained operations can be preferable to a single, more complex one (e.g., a complex regex with a replacer function) if it improves understandability and reduces the potential for future errors.