Two new interactive playground tools:

• playground.html executes JavaScript using this Python library run via Pyodide (so JavaScript in Python in WebAssembly in JavaScript).
• parser-playground.html shows how the micro-javascript tokenizer and parser works with different JavaScript code.

Other changes:

• Fix optional lookahead capture semantics in #9
• Implement iterative parsing to fix deep nesting recursion limits in #10
• JSRegExp(pattern, flags, poll_callback=check_timeout) in #14
• Build JavaScript debugging playground with micropip in #17
• String methods use microjs.regex in #16
• Create interactive playground for tool testing in #18
• Auto-detect theme and reorganize playground demos in #19

• Fix SyntaxError Position Tracking #6
• Resolve Global Eval Scope Issues #7
• Rename JSContext to Context, keep backwards-compatible alias #8

• Documentation improvements for PyPI.

• Initial alpha release.