fix(bundle): transform import.meta.main

[nathanwhit]

For entrypoints, it remains untouched. For non-entrypoints it becomes false.

[Copilot]

Pull Request Overview

This PR adds a new AST transform to rewrite import.meta.main to false for bundled non-entrypoint modules, integrates it into the bundler pipeline, and updates tests to cover the new behavior.

• Introduce BundleTransform in transform.rs to detect and replace import.meta.main for non-entrypoints
• Wire up the transform in cli/tools/bundle/mod.rs, updating loader logic and error variants
• Add end-to-end tests under tests/specs/bundle/import_meta_main

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tests/specs/bundle/import_meta_main/main.ts	Test entrypoint logging import.meta.main
tests/specs/bundle/import_meta_main/a.ts	Test non-entrypoint a.ts export of import.meta.main
tests/specs/bundle/import_meta_main/b.ts	Test non-entrypoint b.ts export of import.meta.main
tests/specs/bundle/import_meta_main/test.jsonc	Expected bundle output and runtime logs
cli/tools/bundle/transform.rs	New AST visitor to replace import.meta.main for non-entrypoints
cli/tools/bundle/mod.rs	Hook up transform, extend loader return types, update error enum