Add TreeSitterPlugin using web-tree-sitter (WASM-based) to extract
structural information from TypeScript and JavaScript files. The plugin
implements the AnalyzerPlugin interface and extracts functions, classes,
imports, exports, and call graphs via AST traversal.
Uses web-tree-sitter instead of native tree-sitter for cross-platform
compatibility (no native compilation required).
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>