fix(kql-to-duckdb): add support for negated string operators

[sushruth]

Summary

Adds complete support for negated string operators and in/!in operators in kql-to-duckdb translator.

Changes

Negated String Operators

• Add handlers for !contains, !startswith, !endswith, !has in expression translator
• Translate to NOT LIKE and NOT REGEXP for valid DuckDB SQL

Array Literals & in/!in Operators

• Add ArrayLiteral expression type to kql-ast
• Update kql-lezer grammar to parse array literals: (value1, value2, ...)
• Add CST-to-AST conversion for ArrayLiteral nodes
• Implement in/!in operator translation to SQL IN/NOT IN

Testing

• Add comprehensive test suite for string operators (12 tests)
• All tests passing:
  • ✅ kql-lezer: 110 tests
  • ✅ kql-to-duckdb: 12 tests

Examples

Negated String Operators

Users | where name !startswith "j"

-- Translates to:
SELECT * FROM Users WHERE name NOT LIKE 'j%'

in/!in Operators

Users | where age in (18, 21, 25)
Users | where age !in (18, 21, 25)

-- Translates to:
SELECT * FROM Users WHERE age IN (18, 21, 25)
SELECT * FROM Users WHERE age NOT IN (18, 21, 25)

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This PR was created by an AI agent on behalf of @sushruth.

[sushruth]

Update: Grammar Generation Automated

The grammar generation process is now fully automated in the build pipeline:

What Changed

• Generated files removed from git: kql.grammar, parser.ts, parser.terms.ts are now gitignored
• Build process automated: bun run build now handles the full pipeline:
  1. generate:grammar - Generate .grammar from TypeScript sources in src/grammar/
  2. build:parser - Generate parser from .grammar using Lezer
  3. fix:parser - Add @ts-nocheck to generated parser
  4. tsc - Compile TypeScript

Developer Workflow

To modify the grammar:

1. Edit TypeScript sources in src/grammar/ (tokens, rules, plugins)
2. Run bun run build
3. Update src/parser/cst-to-ast/ if needed
4. Run bun test

Documentation updated in README.md and CLAUDE.md.

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This comment was created by an AI agent on behalf of @sushruth.