feat: support comment syntax

[YoEight]

Summary

Add support for single-line comments (//) in EventQL queries. Comments are now properly tokenized and discarded during parsing, allowing developers to document their queries inline.

Changes

Lexer

• Added comment() parser function to recognize // style comments
• Handles cross-platform line endings:
• Implemented skip_whitespace_and_comments() to handle any combination of whitespace and comments
• Refactored token() function to use the new whitespace/comment skipper
• Improved lexer error handling with dedicated LexerError type while using the tokenize function

Example

Queries can now include documentation:

// This is a comment that will be discarded by the parser
FROM e IN events
// This is another line that should be ignored
WHERE e.source != "foobar"
// And again another useless comment
PROJECT INTO e