Replace webpack with esbuild for simpler faster builds

[orien]

Context

The extension was using webpack as its bundler, which required ts-loader for TypeScript compilation and had a more complex configuration. Modern VS Code extensions commonly use esbuild for its significantly faster build times and simpler setup.

Changes

• Replaced webpack with esbuild as the bundler
• Created esbuild.js configuration with production/watch modes and problem matcher integration
• Deleted webpack.config.js configuration
• Updated npm scripts:
  • compile now runs type checking followed by esbuild
  • watch now runs esbuild and TypeScript type checking concurrently
  • package runs type checking with production esbuild build
• Updated JavaScript dependencies to latest versions
• Upgraded TypeScript configuration to stricter modern settings (Node16 modules, ES2022, strict mode)
• Applied TypeScript strict mode fixes to extension.ts (proper undefined handling, unused parameter prefixing)

Consequences

• Significantly faster build times during development and CI
• Smaller dependency tree (reduced package-lock.json by many lines)
• Simpler build configuration
• Better type safety with strict TypeScript settings enabled