organize code structure

Maintain clean code organization by moving implementation details to appropriate locations, extracting reusable functionality, and keeping related code together. This improves maintainability and prevents bugs from poor encapsulation.

Key practices:

• Move implementation details to dedicated modules (e.g., move esbuild utilities to bundle/esbuild.rs)
• Extract repeated patterns into reusable functions instead of duplicating code
• Keep struct definitions close to their implementations for better cohesion
• Use named struct fields instead of tuples for public APIs to improve clarity
• Maintain proper encapsulation by keeping internal details private
• Avoid code duplication by centralizing common utilities (e.g., export shared macros from deno_core)

Example of good organization:

// Instead of inline implementation details
pub async fn bundle() -> Result<(), AnyError> {
  // ... lots of esbuild setup code ...
}

// Extract to dedicated module
// bundle/esbuild.rs
pub async fn ensure_esbuild(...) -> Result<PathBuf, AnyError> {
  // esbuild-specific logic here
}

// bundle/mod.rs  
pub async fn bundle() -> Result<(), AnyError> {
  let esbuild_path = esbuild::ensure_esbuild(...).await?;
  // ... main bundling logic ...
}

This approach makes code easier to test, maintain, and understand by grouping related functionality and separating concerns.