[W-19736546] Migrating from tsup to esbuild and consolidating into an npm package

[kylewalke]

What issues does this PR fix or reference?

@W-19736546@

Summary

Migrate build system from tsup to esbuild and consolidate build configurations into a reusable npm package.

Changes

• Created @salesforce/esbuild-presets package containing shared esbuild configurations for Node.js, browser, and web worker targets
• Replaced tsup with esbuild across all packages:
  • apex-ls
  • apex-lsp-shared
  • apex-lsp-vscode-extension
  • apex-parser-ast
  • custom-services
  • lsp-compliant-services
• Removed all tsup.config.ts files and replaced with esbuild.config.ts files
• Updated package.json build scripts and dependencies across all affected packages
• Updated tsconfig.json files to reference correct build outputs
• Added esbuild preset package to turbo.json pipeline
• Renamed test file from tsup-resources.test.ts to esbuild-config-resources.test.ts with updated test logic
• Cleaned up gitignore entries related to old build artifacts
• Updated documentation in README files to reflect new build system

Testing

All existing tests pass with the new build system. Build artifact tests updated to validate esbuild output instead of tsup output.